Algebraic Fractions (Equations) - GCSE Higher Maths

1st Class Maths
1 Nov 202318:41

Summary

TLDRThis instructional video teaches viewers how to solve equations involving algebraic fractions. It begins by combining fractions on the left side of an equation using a common denominator, then simplifies and solves for the variable. The video progresses through multiple examples of increasing difficulty, including those with quadratic equations that require factorization or the use of the quadratic formula. It concludes with solving equations with complex denominators and provides a step-by-step approach to finding the solutions. The video aims to equip learners with the skills to tackle a variety of algebraic fraction problems.

Takeaways

  • πŸ“š The video is a tutorial on solving equations with algebraic fractions.
  • πŸ”— It builds upon a previous video titled 'algebraic fractions operations', which is linked in the description for reference.
  • πŸ“‰ The initial step involves focusing on the left-hand side of the equation and combining fractions by finding a common denominator.
  • πŸ“Œ To combine fractions, the video demonstrates converting each fraction to have a common denominator, often the least common multiple (LCM) of the original denominators.
  • πŸ“ The process includes multiplying both the numerator and the denominator by appropriate factors to achieve the common denominator.
  • βž— After combining the fractions, the video shows how to expand and simplify the resulting expressions.
  • πŸ”’ The video provides step-by-step solutions to various equations, including multiplying both sides by the denominator to eliminate fractions.
  • πŸ“ˆ It explains how to handle equations with quadratic expressions, including factorization and the use of the quadratic formula.
  • 🎯 The video also covers how to deal with equations that result in a quadratic that does not factorize easily, requiring the quadratic formula or completing the square.
  • πŸ“Š For complex equations, the script illustrates the process of expanding brackets and simplifying terms before solving.
  • πŸ“‘ The video concludes with a series of examples that incrementally increase in difficulty, guiding viewers through the problem-solving process.

Q & A

  • What is the main topic of the video?

    -The main topic of the video is solving equations that contain algebraic fractions.

  • What should viewers do if they are not familiar with algebraic fractions operations?

    -Viewers should check out the previous video titled 'algebraic fractions operations' which is linked in the description of the current video.

  • What is the first step in solving an equation with algebraic fractions according to the video?

    -The first step is to focus on the left-hand side of the equation and combine the fractions into one fraction over a common denominator.

  • How is the common denominator found for fractions with denominators 6 and 4?

    -The common denominator is found by determining the least common multiple of the denominators, which in this case is 12.

  • What is the process of rewriting fractions over a common denominator?

    -Each fraction is rewritten by multiplying both the numerator and the denominator by the factor needed to reach the common denominator.

  • How does the video handle the right-hand side of the equation initially?

    -The right-hand side of the equation is left alone initially while the left-hand side is combined into one fraction.

  • What mathematical operation is used to simplify the numerator after combining fractions?

    -The video uses expansion of brackets and then collects like terms to simplify the numerator.

  • Why is it necessary to multiply both sides of the equation by 12 after combining fractions?

    -Multiplying both sides by 12 eliminates the fraction and makes the equation simpler to solve.

  • What is the solution to the first example equation provided in the video?

    -The solution to the first example equation is x = 27/5, which is 5.4.

  • How does the video approach a more complex equation with denominators 6 and 9?

    -The video uses the same approach of finding a common denominator, which is the least common multiple of 6 and 9, and then combines the fractions on the left-hand side.

  • What is the common mistake to avoid when expanding brackets in equations with algebraic fractions?

    -The common mistake to avoid is incorrectly handling the signs when multiplying terms, especially with subtraction involved.

  • How does the video handle equations with quadratic expressions?

    -The video shows how to set the quadratic expression equal to zero and then solve for x using methods such as factorization or applying the quadratic formula.

  • What is the final form of the solution that the video demonstrates for a particularly tricky equation?

    -The final form of the solution for the tricky equation is x = a + b√13/b, where a and b are specific numerical values derived from the quadratic formula.

  • How does the video simplify the square root term in the quadratic formula?

    -The video simplifies the square root term by factoring out common factors and using the properties of square roots to express the term in its simplest form.

  • What is the process for solving the last equation in the video?

    -The process involves combining fractions over a common denominator, expanding and simplifying the numerator, multiplying both sides by the denominator to clear the fraction, and then solving the resulting quadratic equation.

  • What are the two solutions to the final equation presented in the video?

    -The two solutions to the final equation are x = 8.5 and x = 1/3.

Outlines

00:00

πŸ“š Introduction to Solving Algebraic Fraction Equations

This paragraph introduces the topic of solving equations involving algebraic fractions. It suggests reviewing a previous video on algebraic fraction operations and outlines the process of combining fractions on the left-hand side of an equation by finding a common denominator. The example given demonstrates converting fractions with denominators 6 and 4 into a common denominator of 12, combining them, and then solving the resulting equation to find x = 5.4.

05:00

πŸ” Expanding and Simplifying Equations with Algebraic Fractions

This section builds upon the initial approach by tackling a more complex equation with fractions having denominators of 6 and 9. The common denominator is determined to be 18, and the fractions are rewritten and combined accordingly. After expanding and simplifying the equation, the solution process involves multiplying both sides by 18 and isolating x to find x = 4.

10:04

πŸ“˜ Solving Equations with Multi-term Denominators

The paragraph delves into solving equations where denominators have multiple terms, such as x + 2 and x + 5. The least common multiple of these is used as the common denominator, and the fractions are rewritten and combined. After expanding and simplifying, the equation is transformed into a quadratic equation. The process of solving this quadratic equation involves setting it to zero and factoring it to find two solutions, x = -4 and x = 1.

15:04

🧩 Advanced Quadratic Equations and Their Solutions

This part of the script addresses even more challenging equations with complex denominators. The equation is transformed into a quadratic form, and the quadratic formula is introduced as the method for solving it. The coefficients are identified, and the formula is applied to find the solutions in a specific form, a + b√13/c. The final answer is simplified to match the form requested in the question.

πŸ”‘ Final Challenge: Solving a Complex Fraction Equation

The final paragraph presents a complex equation with fractions on both sides. The common denominator is established, and the equation is simplified into a single fraction. After multiplying through by the denominators to clear the fractions, the resulting quadratic equation is solved by setting one side to zero and factoring. The solutions are found by setting each factor equal to zero, yielding x = 8.5 and x = 1/3.

Mindmap

Keywords

πŸ’‘Algebraic Fractions

Algebraic fractions refer to expressions that represent the division of two algebraic expressions. In the context of this video, they are the core subject matter, with the script focusing on solving equations that contain these fractions. The video aims to teach viewers how to combine and simplify algebraic fractions to solve equations, as demonstrated through various examples where fractions with different denominators are combined into a single fraction with a common denominator.

πŸ’‘Common Denominator

A common denominator is a shared denominator for two or more fractions, which allows for their combination into a single fraction. The script emphasizes the importance of finding the least common multiple (LCM) of the denominators to create a common denominator. This is a fundamental step in solving equations with algebraic fractions, as it simplifies the process of combining fractions on one side of the equation.

πŸ’‘Lowest Common Multiple (LCM)

The lowest common multiple is the smallest number that is a multiple of each of the numbers involved. In the script, the LCM is used to determine the common denominator when combining fractions. For instance, the LCM of 6 and 4 is 12, which is then used as the common denominator to rewrite and combine the fractions, illustrating the practical application of LCM in solving algebraic equations.

πŸ’‘Expanding Brackets

Expanding brackets involves distributing the terms inside the brackets across the terms outside, following the distributive property of multiplication over addition or subtraction. The script demonstrates this process as part of solving equations with algebraic fractions, where brackets are expanded to simplify the equation and facilitate further steps in the solution process.

πŸ’‘Quadratic Equation

A quadratic equation is a polynomial equation of degree two, typically in the form of ax^2 + bx + c = 0. The script introduces quadratic equations as a result of simplifying and expanding algebraic fractions. The video provides examples of how to manipulate these equations to find their solutions, either by factorization or by using the quadratic formula.

πŸ’‘Quadratic Formula

The quadratic formula is used to solve quadratic equations and is given by x = (-b ± √(b^2 - 4ac)) / (2a), where a, b, and c are coefficients of the quadratic equation. The script mentions the quadratic formula as a method to find the solutions for equations that do not factorize easily, showcasing its application in the context of solving more complex algebraic equations.

πŸ’‘Factorization

Factorization is the process of breaking down a polynomial into a product of its factors. In the script, factorization is used as a method to simplify quadratic equations and find their solutions. The video demonstrates how certain quadratic equations can be factorized into simpler expressions, leading to the determination of the variable's value.

πŸ’‘Solving Equations

Solving equations involves finding the values of the variables that make the equation true. The script's main theme revolves around solving equations with algebraic fractions. The process involves combining fractions, expanding brackets, simplifying expressions, and using various algebraic techniques to isolate the variable and find its value.

πŸ’‘Like Terms

Like terms are terms in a polynomial that have the same variables raised to the same power. The script discusses collecting like terms as part of the process of simplifying equations. This simplification is crucial for combining terms and making the equation easier to solve, as demonstrated in the video's examples.

πŸ’‘Completing the Square

Completing the square is a method used to solve quadratic equations by transforming the quadratic expression into a perfect square trinomial plus a constant. While the script does not explicitly use this method in the examples provided, it is mentioned as an alternative approach to solving quadratic equations that do not easily factorize.

πŸ’‘Difference of Squares

The difference of squares is a special algebraic identity where the difference between two squared terms can be factored into the product of two binomials. The script mentions this concept in the context of expanding brackets and simplifying expressions, which is a useful technique for solving equations involving squared terms.

Highlights

Introduction to solving equations with algebraic fractions.

Building upon previous video on algebraic fractions operations.

Combining fractions with different denominators into one.

Finding the least common multiple (LCM) for denominators.

Rewriting fractions with a common denominator of 12.

Combining fractions over a common denominator to simplify equations.

Expanding brackets and collecting like terms to simplify equations.

Multiplying both sides by the denominator to clear fractions.

Solving a straightforward equation to find x = 27/5.

Approach to solving more complex equations with algebraic fractions.

Using the LCM of denominators 6 and 9, which is 18.

Combining fractions with a common denominator of 18.

Expanding and simplifying equations to solve for x.

Solving a quadratic equation by setting one side to zero.

Finding solutions to a quadratic equation using factorization.

Increasing difficulty with denominators that are binomial expressions.

Multiplying fractions with binomial denominators to find a common denominator.

Expanding and simplifying complex algebraic fractions.

Solving equations with quadratic results using the quadratic formula.

Using the quadratic formula to find solutions for x.

Simplifying square root expressions in the quadratic formula.

Final example with a complex equation requiring a common denominator approach.

Expanding and simplifying a complex equation with multiple terms.

Solving a quadratic equation with large coefficients.

Factorizing a quadratic equation to find possible solutions for x.

Finding two solutions for x by setting each factor equal to zero.

Conclusion and encouragement to try exam questions linked in the description.

Transcripts

play00:00

[Music]

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in this video we're going to learn how

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to solve equations that have algebraic

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fractions in them this video is going to

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build upon a previous video the one

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titled algebraic fractions operations

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I'll put a link in this video's

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description just in case you want to

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check that one out

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first so let's take an equation that has

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some algebraic fractions in it what

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we're going to do is focus on the left

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hand side first of all and try and

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combine these into one fraction to do

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this we need to make sure we have a

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common denominator at the moment the

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denominators are 6 and four the lowest

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common multiple of these is 12 so we

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could rewrite the left hand side as two

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fractions that are both over 12 if we

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compare these two fractions here to get

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from 6 to 12 on the bottom we must have

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multiplied by two so we need to multiply

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the top by two so that's 2 lots of x + 3

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for the second fraction on the bottom to

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get from 4 to 12 we've multiplied by

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three so we multiply by three on the top

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three lots of x + 1 and the right hand

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side is still equal to

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three now that we have the common

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denominator we can combine these into

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one big fraction all over 12 so we've

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got two lots of x + 3 in between them we

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have a plus sign and then three lots of

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x + 1 and the right hand side is still

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equals 3 next we need to expand the

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brackets so I'm going to write the over2

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and the equals 3 and then we're going to

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expand the numerator here so we've got

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two lots of x that's 2x two lots of

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postive 3 that's POS 6 then we've got a

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postive 3 * X that's POS 3x and then

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pos3 * pos1 that's

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pos3 we can now tidy up that numerator a

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bit by collecting like terms so if we

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write the over 12 and equals 3 we've got

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2X and 3X that adds to make 5x and then

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we've also got a six and a plus three

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which gives you 9 we've now turned this

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into a relatively straightforward equ

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equation to solve we can multiply both

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sides by 12 to get rid of that fraction

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if you multiply by 12 on the left you

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get 5x + 9 and if we multiply by 12 on

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the right 3 * 12 is 36 then just

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subtract 9 from both sides this will

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give you 5x = 27 and then divide both

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sides by 5 and this gives you x = 27 / 5

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which is 5.4 so the solution to this

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equation is

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5.4 now let's try another example that's

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a bit more tricky so for this one we're

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going to use the same Approach at first

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we're going to leave the right hand side

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alone and try and combine the left hand

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side into one big fraction looking at my

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denominators this time of 6 and 9 the

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lowest common multiple is 18 so I'm

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going to write both of these as

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something over 18 for the first fraction

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to get from 6 to 18 we multiply by three

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so we need to multiply X+ 2 on the top

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by three as well so three lots of X+ 2

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for the second fraction to get from 9 to

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18 we multiply by two so we need two

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lots of the top so two lots of x - 1 and

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keep that right hand side the same equal

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2/3 now we have that common denominator

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we can combine them into one big

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fraction all over 18 so we have three

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lots of x + 2 then in between them a

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subtraction sign and then two lots of x

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- one and keep that right hand side the

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same that's

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2/3 then as we did before we're going to

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expand those brackets so we'll write the

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over 18 and the 2/3 down and then expand

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these brackets we've got three lots of X

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that's 3x three lots of pos2 that's plus

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6 then we have -2 * X that's -2X and you

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have to be really careful on this one

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this is a really common mistake -2 * -1

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is

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positive2 then as before we'll collect

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the like terms on the numerator so

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everything else can be written down as

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the same and then on the top we've got

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3x - 2x that's just 1 x and then we've

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got 6 + 2 which is 8 the next thing I

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would do here is multiply both sides by

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18 if we multiply by 18 on the left that

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will cancel the 18 that's there so we

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just have x + 8 and if you multiply the

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right hand side by 18 we've got 2/3

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multiplied by 18 that's just the same as

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2/3 of 18 2/3 of 18 is 12 finally if we

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subtract 8 from both sides we end up

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with the answer x =

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4 now let's increase the difficulty once

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more and have a look at this question

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here when we look at the denominators of

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these fractions we can see they both

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have two terms this means to find their

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lowest common multiple we're going to

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need to multiply them together so both

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of these fractions can be Rewritten as

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something over x + 2 x + 5 let's look at

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the left fraction first so this one to

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get from x + 2 to x + 2 * x + 5 we

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obviously multiply by x + 5 so we need

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to do this on the top as well so we need

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four lots of x + 5 and then we can look

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at the second fraction so to get from x

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+ 5 to x + 2 * x + 5 we multiply by x +

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2 so on the top we need to multiply by

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x+2 as well and that's four lots of x+2

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and of course the right hand side is

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still just

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two now that we have this common

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denominator we can write them as one big

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fraction all over x + 2 x + 5 so on the

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numerators we have four lots of X+ 5

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then in between them we have a plus sign

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and then four lots of X+ 2 and the right

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hand side is still equals 2 we can now

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do some expanding and then simplifying

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so if we expand out the numerator we've

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got 4 * X which is 4X 4 * 5 which is +

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20 4 * X which is 4X again and then 4 *

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2 that's a positive

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8 next we need to do the simplifying of

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the numerator so on the top here we have

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4x + 4x which is 8 x and then we also

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have 20 + 8 which is

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28 next we're going to multiply both

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sides of this equation by both of those

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brackets that are on that denominator so

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by X+ 2 and x + 5 this will clear the

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fraction on the left hand side to give

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us 8x +

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28 but on the the right hand side we'll

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have two lots of x + 2 x + 5 next we'll

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leave the left hand side alone and then

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we've got two lots and then we'll expand

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those brackets and whatever we get will

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go inside this much larger bracket here

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so if we expanded that double bracket

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we'd have x * X that's x 2 we then have

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x * 5 which is 5 x and 2 * X which is 2

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X and 5 x and 2 x adds to make 7 x and

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then finally we'd have 2 * 5 which is 10

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on the right hand side we can then

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expand this bra ET so if we leave the

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left hand side alone on the right hand

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side we have two lots of everything

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that's in that bracket so two lots of

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x^2 two lots of 7 x that's 14x two lot

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of 10 that's 20 you can now see we have

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a quadratic equation to solve when we

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solve these we need to set one of the

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sides equal to zero since the 2x^2 is on

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the right hand side I'm going to make

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the left hand side equal to zero to do

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this I need to take away 8X and also

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take away 28 from both sides if I took

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away those from the left hand side I'd

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get zero and if if I take those away

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from the right hand side the 2x^2 will

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remain unchanged but then I need to take

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the 8X away from the 14x which is 6X and

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then take the 28 away from the 20 which

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is8 now there's a common factor of two

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here to all terms so I can divide both

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sides by two if I divide the left hand

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side by two 0id by 2 is still 0o but

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then on the right hand side 2x^2 ID 2 is

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1 x^2 6X / 2 is 3x and8 ID 2 is -4

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fortunately for us this quadratic will

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factorize so on the left hand side we

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have zero and the right hand side will

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factorize to give x + 4 x -1 this leads

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us to two solutions either the first

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bracket is zero so x + 4 equal 0 in

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which case X is -4 or the second bracket

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equals 0 so X - 1 = 0 gives us the

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solution X =

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pos1 now let's have a look at an even

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trickier question so for this one we

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need to solve an equation but we've told

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we need to give the answer in a

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particular form

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a plus orus < TK 13 / B this is a clear

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indication that when we get to a

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quadratic at the end it's not going to

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factorize anymore we either need to use

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the quadratic formula or complete the

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square to get the solutions so let's go

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ahead and try and solve this one so

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first of all we'll look at those

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denominators and we can see we've got x

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+ 3 x - 3 so the product of those will

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become our

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denominators then we compare the first

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fractions so to get from x + 3 to x + 3

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x - 3 we multiply by x - 3 so we need to

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multiply that six on the top by x - 3

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and when we compare the second fractions

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this time we've multiplied by x + 3 so

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on the top we need two lots of x + 3 and

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this equals 3 now we can combine them

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into one big fraction over that common

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denominator we have 6 lots of x - 3 in

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between the fractions is a subtraction

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sign and then 2 lots of x +

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3 now we can expand out those brackets

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so on the top we've got 6 * X that's 6 x

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6 * -3

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8 -2 * x -2X and a -2 * a POS 3 that's

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A6 then we can collect those like terms

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so on the top we've got 6X take 2x

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that's 4X and then -8 subtract 6 that's

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-4 then we would multiply both sides by

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that denominator x + 3 x - 3 this will

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clear the fraction on the left hand side

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so you've just got 4x - 24 but on the

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right hand side we have three lots of x

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+ 3 x - 3 to solve this we'll leave the

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left hand side alone and on the right

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hand side we've got three lots of

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whatever we get when we expand these two

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brackets well this one's the difference

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of two squares if we do x * X we get x2

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and then we have x * -3 -3x but also

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posi 3 * X which is postive 3x so those

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X terms will cancel and then we have 3 *

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3 which is 9 so we have 4x - 24 and then

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if we expand this bracket three L of x^2

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is 3x^2 and 3 lot of -9 is

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-27 so you can see we do have a

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quadratic and we need to get one of the

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sides to be equal to zero once again I'm

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going to make that the left hand side so

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to make the left hand side equal to zero

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I would need to subtract 4X and then add

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24 to both sides so if I do that on the

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left I get zero of course and on the

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right hand side I get 3x^2 that remains

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unchanged then I subtracted 4X and

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there's no X term there already so

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that's just -4x and then we need to add

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24 to -27 which gives us -3 so we end up

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with this quadratic equation here to

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solve now remember we know from the form

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they want the answer in we need to solve

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this using the formula or completing the

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square and this one's probably going to

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be much easier using the quadratic

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formula so we need to find the values of

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a b and c they're the coefficients of X2

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X and the constant term so the

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coefficient of X2 is 3 the coefficient

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of x is -4 and the constant term at the

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end is -3 so a is 3 B is-4 and C is -3

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now we can substitute those values into

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the quadratic formula it's x equal

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negative B well B is already negative so

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if we did negative B it will become

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positive so it's actually a positive 4

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plus or minus the square root of then

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b^2 so -4 2 subtract four lots of a

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which is 3 multipli C which is -3 and

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all of this is divided by two lots of a

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a and 2 lot of a is 2 lots of three so

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six now this question would actually be

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a non-calculator question so we're going

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to need to work out the value of the

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number that's inside that square root so

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let's write x = 4 plus or minus the < TK

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of over 6 but we'll work out what's

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inside that square root so if we did -4

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squar that would be -4 multiplied by

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itself so

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16 and then if we did4 multipli by 3

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that's -12 and then multiply that by -3

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that becomes a positive

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36 so we end up with 16 + 36 inside that

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square root you can add those two

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together that's 52 so x = 4 plus or- <

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TK 52 / 6 next what we need to do is

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simplify that < TK 52 so using our third

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rules if we take root 52 that could be

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expressed Asun 4 multiplied

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byun3 the square < TK 4 is just two so

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this is 2 < tk13 so in place ofun 52 we

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could write 2K3 so it's X = 4 plus orus

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2un 13 now over 6 now this is looking a

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lot like the answer but we're still not

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quite there that one just has 1 < TK 13

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and we have two the reason for that is

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we have a common factor of two here if

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we divide all terms by two we get x

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equals if we divide the four by two we

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get two divide 2 < tk3 by two you get

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1un 13 and divide 6 by two you get three

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this answer now matches the form we were

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asked in the question you can see the

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value of a is 2 2 and the value of B is

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three now we're going to look at one

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more final question this one here we're

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going to start this one how we started

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all of the previous questions we're

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going to write the left hand side over a

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common denominator so for this one it'll

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be the product of x + 17 and 2x -

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5 so if we compare these first two

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fractions you can see we've multiplied

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by 2x - 5 so if we multiply by 2x - 5 on

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the top we get 3 x lots of 2x -

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5 and and for the right fractions when

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we compare these we've multiplied by x +

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17 so we need three lots of x + 17 and

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the right hand side is equal to 3 over

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4 now we have that common denominator we

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can write them as one big fraction so

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we've got 3x and then brackets 2x - 5

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then we have a subtraction in between

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them and 3x +

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17 next we're going to expand out that

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numerator so we'll write everything else

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the same we have 3x * 2x that's 6 x^2 3x

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* -5 that's

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15x -3 * X -3x and -3 * pos7 is

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-51 now there's a little bit of

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simplifying we can do on the numerator

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so we can't simplify the 6x2 that's the

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only term of x^2 but we can simplify -5x

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subtract 3x which is -8x and then

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subtract

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51 so now we've written the left hand

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side as a single fraction what we're

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going to do next is multiply both sides

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by both of those brackets on that

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denominator so if we multiply the left

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hand side by x + 17 and 2x - 5 that will

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clear the fraction so we've got 6x^2 -

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18x - 51 and on the right hand side

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we've just multiplied this

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3/4 by both of those brackets now in the

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previous couple of questions we haven't

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had to deal with a fraction like this on

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the right hand side it was just an

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integer before those two brackets to

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deal with this fraction you can just

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multiply both sides by four if we

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multiply the left hand side by four we

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get four lots of the left hand side and

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if we multiply the right hand side by

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four that four will cancel so we've just

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got three lots of those two

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brackets now we've got lots of expanding

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to do so on the left hand side we need

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to multiply by four so we've got four

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lots of 6x^2 that's 24 x^2 four lots of

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-8x that's - 72x and four Lots of- 51 is

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-24 then on the right hand side we're

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going to write a three and then a big

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bracket then expand out the double

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bracket and write the terms inside this

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big bracket ET so we've got x * 2x first

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that's

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2x^2 then we would do x * -5 so -5x but

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we would also do 17 * 2x which is a

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positive

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34x so we've got - 5x + 34x that's

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positive

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29x and finally 17 * -5 is

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85 we can leave that left hand side

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alone and expand this bracket on the

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right hand side we need to multiply by

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three this time 3 lots of 2x^2 is 6x^2 3

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lots of 29x is 87x and 3 lots of 85 is -

play16:05

255 so we do end up with a quadratic

play16:07

equation to solve since we have more X

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squs on the left hand side I'm going to

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make the right hand side equal to zero

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on this one so i' need to subtract 6x^2

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subtract 87x and add 255 to both sides

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so on the left hand side if I subtract 6

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x^2 from 24 x^2 I get 18 x^2 and then if

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I subtract 87x from the 72x we get

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159x and then if we add 255 to ne24 we

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end up with a positive 51 and the right

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hand side we know will equal

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zero now let's take that quadratic

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equation and we're going to solve it

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this one does look really nasty because

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of the size of the numbers but there is

play16:49

actually a common factor of three here

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if you divide 18 x^2 by 3 you get 6 x^2

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divide -9x by 3 that's - 53x and divide

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the 51 by 3 that's 17 and of course if

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you divide 0 by three that's still zero

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so we're going to factorize this one

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actually it will factorize into two

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brackets now it's actually quite

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fortunate we have a 17 at the end since

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we have a 17 that's a prime number we

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know its factors are only 1 and 17 so if

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it did factorize the only possible

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numbers we could put at the end of these

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brackets would be 1 and 17 and they

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would actually both be negative as well

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since a negative times a negative gives

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you a positive so we still get a

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positive 17 but the only way we'd end up

play17:28

with a 53x is if we had negative terms

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here if they were both positive that 53x

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wouldn't be attainable so we can put 17

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and Ne -1 in these brackets and then we

play17:38

just need to think about a few of the

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different combinations to try and get

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that 6x^ s so we're either going to use

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a 6X and a 1x or a 3X and a 2x now if

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you try a few different combinations out

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it shouldn't take you too long to

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realize we need 2x - 17 and 3x - 1 if

play17:54

you won't give this a go and expand it

play17:56

out and you'll see it does give that

play17:57

quadratic a b

play17:58

so finally to get our two solutions we

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need to set the first bracket equal to 0

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so 2x - 17 = 0 or the second bracket

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equal to 0 so 3x - 1 = 0 to solve the

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left one you can add 17 to both sides

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and get 2x = 17 and then divide both

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sides by two to get x = 8.5 for the

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right one you can add one to both sides

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so 3x = 1 and divide both sides by 3 to

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get x =

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1/3 thank you for watching this video I

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hope you found a useful check out the

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one I think you should watch next

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subscribe so you don't miss out on my

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future videos and now go ahead and try

play18:33

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description

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