Algebra 1 Basics for Beginners

UltimateAlgebra
20 Nov 202323:05

Summary

TLDRThis Ultimate Algebra video offers a comprehensive guide to solving Algebra 1 problems efficiently. It covers solving one-step equations, multi-step equations, inequalities, and graphing. The video emphasizes mastering basic operations like addition, subtraction, multiplication, and division to isolate variables. It also teaches how to handle absolute values and radicals in equations. Practical examples include determining the number of gallons per box and Michael's age from word problems. The video concludes with a discussion on functions, explaining what qualifies as a function and providing examples. Viewers are encouraged to deepen their understanding with Ultimate Algebra's full course.

Takeaways

  • 📘 Solving one-step equations involves isolating the variable by performing the opposite operation on both sides of the equation.
  • 🔢 For two-step equations, the order of operations is crucial, and you should eliminate terms step by step, starting with addition or subtraction.
  • 📐 When dealing with equations that include exponents, isolate the term with the exponent and then apply the opposite operation, such as taking the root.
  • 🔄 To solve equations with multiple representations of the variable, move all variable terms to one side and constants to the other.
  • 📊 Absolute value equations require setting up two separate equations, one with the expression inside the absolute value being positive and the other negative.
  • 🌐 For radical equations, isolate the radical and then square both sides of the equation to eliminate the radical.
  • 📑 Rational equations often involve eliminating fractions by finding a common denominator or cross-multiplying.
  • 📈 Transposing formulas to solve for a specific variable involves moving terms to the other side of the equation using opposite operations.
  • 📉 Solving inequalities follows similar steps to solving equations, but remember to reverse the inequality sign when multiplying or dividing by a negative number.
  • 📋 Graphing inequalities on a number line involves placing an open or closed circle at the critical point and drawing an arrow in the direction of the inequality sign.
  • 📝 Word problems often require identifying key values and setting up equations to find the unknown, such as calculating the number of gallons per box.

Q & A

  • How do you solve a one-step equation like x + 2 = 5?

    -To solve a one-step equation, isolate the variable by performing the opposite operation on both sides. For x + 2 = 5, subtract 2 from both sides to get x = 3.

  • What is the order of operations and how does it help in solving equations?

    -The order of operations is a rule in mathematics that dictates which operations to perform first. It helps in solving equations by determining the sequence of operations to reverse when isolating the variable.

  • How do you solve a two-step equation like 2x + 3 = 11?

    -First, eliminate any addition or subtraction terms by performing the opposite operation. Then, isolate the variable by dividing both sides by the coefficient of the variable.

  • What is the process for solving multi-step equations?

    -Solve multi-step equations by isolating the variable on one side of the equation. This involves reversing the order of operations, starting with addition or subtraction, then multiplication or division, and finally dealing with exponents.

  • How do you handle equations with the variable represented more than once, like 4x + 5 = 9 + 2x?

    -Move all variable terms to one side and constants to the other side. For 4x + 5 = 9 + 2x, subtract 2x from both sides to combine like terms, then solve for x.

  • How do you solve absolute value equations?

    -Treat the absolute value as both positive and negative of the value on the other side of the equation. Solve both resulting equations to find the possible values of the variable.

  • What is the key to solving rational equations?

    -To solve rational equations, eliminate the fractions by finding a common denominator or by cross-multiplying, then solve for the variable.

  • How do you approach solving inequalities?

    -Solve inequalities similarly to equations, but remember to reverse the inequality sign when multiplying or dividing by a negative number.

  • Can you explain how to graph an inequality on a number line?

    -Graph an inequality by placing a circle at the critical point and drawing an arrow in the direction indicated by the inequality sign. Use an open circle for 'greater than' or 'less than' and a closed circle for 'greater than or equal to' or 'less than or equal to'.

  • How do you solve word problems that involve packaging items into groups, like shipping 2,500 gallons into boxes?

    -Identify the total amount, the number of groups (boxes), and any remainder. Set up an equation with the group size as the variable, and solve for the variable to find the amount per group.

  • What is the definition of a function in algebra?

    -A function in algebra is a relation where each input value corresponds to exactly one output value. No input value can have multiple output values.

Outlines

00:00

🧮 Introduction to Solving Algebra 1 Problems

This paragraph introduces the video, explaining that it focuses on solving Algebra 1 questions in the simplest way. Viewers are encouraged to explore the Ultimate Algebra course for a more in-depth understanding. The first problem, a simple one-step equation (x + 2 = 5), is solved by isolating x through subtraction of 2 from both sides, resulting in x = 3.

05:01

➗ Solving Two-Step Equations

The second paragraph demonstrates solving a two-step equation (2x + 3 = 11). The process is explained step by step using the reverse order of operations, beginning by eliminating addition (subtracting 3) and then removing multiplication (dividing by 2), resulting in x = 4.

10:04

🔢 Solving Multi-Step Equations

This paragraph explains how to solve a multi-step equation (3x² + 8 = 20). The order of operations is reversed, first subtracting 8, then dividing by 3, and finally taking the square root to solve for x, giving x = 2.

15:06

✖️ Solving Equations with X on Both Sides

The fourth paragraph introduces equations where x appears on both sides (4x + 5 = 9 + 2x). The approach is to move all terms containing x to one side, and then solve the resulting two-step equation. The solution yields x = 2.

20:10

📐 Solving Absolute Value Equations

This paragraph covers solving absolute value equations. In the example (|x + 3| = 7), the equation is split into two cases: x + 3 = 7 and x + 3 = -7. Solving both cases results in x = 4 and x = -10.

➕ Handling Absolute Value with Additional Terms

Here, a more complex absolute value equation is presented (|x + 1| + 6 = 9). The first step is to isolate the absolute value by subtracting 6 from both sides. Then, the equation is split into two cases, resulting in x = 2 and x = -4.

🧮 Solving Radical Equations

This paragraph explains solving radical equations (√(x + 3) = 3). First, the equation is simplified by isolating the radical, squaring both sides, and then solving the resulting one-step equation to find x = 6.

➗ Solving Rational Equations

The focus here is on solving rational equations (4/(x - 5) = 3/x). Cross multiplication is used to eliminate the fractions, resulting in a linear equation, which is solved to find x = -5.

📏 Changing the Subject of a Formula

This paragraph explains how to solve for x in a formula (y = mx + b). Using the reverse order of operations, the first step is to move b by subtraction, and then divide by m, resulting in x = (y - b)/m.

📉 Solving Inequalities

This section covers solving inequalities (-3x + 1 > 7). The process is similar to solving equations, but it includes the rule that when dividing by a negative number, the inequality sign flips. The solution is x < -2.

🔀 Solving Compound Inequalities

Here, the method of solving compound inequalities (-3 < x + 8 < 20) is explained. The same operation (subtracting 8) is applied to all three parts of the inequality, leading to the solution -11 < x < 12.

📊 Graphing Inequalities on a Number Line

This paragraph introduces graphing inequalities, using the example x > -4. The number line is drawn with an open circle at -4 (indicating x is greater but not equal) and an arrow pointing to the right.

📦 Solving Word Problems with Two-Step Equations

This section walks through a two-step word problem involving the packaging of 2,500 gallons of product into 20 boxes, with 100 gallons left over. By setting up and solving the equation 20x + 100 = 2,500, the solution for x (gallons per box) is 120.

👶 Solving Age-Related Word Problems

This paragraph explains how to solve an age-related word problem: 'Five added to thrice Michael's age is 50.' The equation 5 + 3x = 50 is solved step by step, resulting in Michael's age being 15 years.

🔁 Identifying Functions from Relations

The final paragraph explains how to identify if a relation is a function. It emphasizes that each input value must have only one output value, and gives an example where one input has two outputs (making it not a function). The answer to the example question is C.

Mindmap

Keywords

💡One-step equations

One-step equations involve solving for the unknown variable in just one step, such as using addition, subtraction, multiplication, or division. In the video, these are foundational for understanding algebra, with examples like 'x + 2 = 5,' where subtracting 2 from both sides quickly solves for x.

💡Order of operations

The order of operations is the sequence in which different mathematical operations are performed. This is crucial in solving multi-step algebra problems. The video highlights its importance, demonstrating how addition and multiplication must be approached in reverse when solving equations like '2x + 3 = 11.'

💡Opposite operations

Opposite operations refer to the idea of using inverse functions (like addition vs. subtraction or multiplication vs. division) to move terms from one side of an equation to the other. In the video, it is emphasized as a fundamental technique for simplifying equations, such as subtracting 3 from both sides of 'x + 3 = 7.'

💡Multi-step equations

Multi-step equations require more than one operation to isolate the variable. The video uses '3x^2 + 8 = 20' as an example, explaining how to break down the steps by reversing the order of operations, starting with subtraction, then division, and finally addressing the exponent.

💡Absolute value

Absolute value refers to the non-negative value of a number, regardless of its sign. The video shows how to solve absolute value equations by considering both the positive and negative solutions, as in 'x + 3 = 7 and x + 3 = -7.'

💡Radical equations

Radical equations involve a variable inside a radical (such as a square root). The video demonstrates how to handle these, explaining the process of isolating the radical before squaring both sides to eliminate the square root, as shown in '√(x + 3) = 3.'

💡Rational equations

Rational equations feature variables in the denominator of fractions. The video explains how to solve these by cross-multiplying, as in the example '4/(x - 5) = 3/x,' showing how to eliminate fractions and simplify.

💡Inequalities

Inequalities are mathematical expressions that use symbols like '>' or '<' to compare values. In the video, inequalities are solved similarly to equations, with special attention to how multiplying or dividing by a negative number flips the inequality sign, as seen in '-3x + 1 > 7.'

💡Graphing inequalities

Graphing inequalities involves representing the solutions of an inequality on a number line. The video illustrates this concept by explaining how to use open or shaded circles depending on whether the inequality includes equality (e.g., 'x > -4' is represented with an open circle).

💡Functions

A function is a relation where each input has exactly one output. The video discusses how a relation can be checked for being a function, showing that if an input like 'x = 3' has two outputs (e.g., 6 and 8), it is not a function, reinforcing the concept that functions have unique outputs for each input.

Highlights

Introduction to solving Algebra 1 questions using the easiest methods.

Explanation of solving one-step equations by isolating the variable.

Demonstration of how to perform the opposite operation to isolate variables.

Emphasis on the importance of mastering one-step equations for math tests.

Guide on solving two-step equations, such as 2x + 3 = 11.

Introduction to the order of operations and its role in solving equations.

Process of solving multi-step equations like 3x^2 + 8 = 20.

Explanation of how to handle equations with variables represented twice.

Approach to solving absolute value equations.

Method for solving radical equations with variables inside a radical sign.

Technique for solving rational equations with variables in the denominator.

How to change the subject or transpose formulas to solve for a specific variable.

Process of solving inequalities, including handling negative numbers.

Guide on solving combined inequalities.

Instructions on graphing inequalities on a number line.

Example of solving a word problem involving packaging gallons into boxes.

Explanation of how to quickly solve word problems using a two-step equation.

Method for solving age-related word problems using algebraic equations.

Criteria for determining whether a relation is a function or not.

Identification of relations that are not functions due to multiple output values for the same input.

Encouragement to get the full course for mastering algebra.

Transcripts

play00:00

welcome to another video from Ultimate

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algebra.com in this video we will be

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looking at how to answer Algebra 1

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questions the easiest way please this

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video will not be exhaustive for a

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complete course deeper dive with more

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examples please check out our ultimate

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algebra course at ultimate algebra.com

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let's Dive Right

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In question 1 x + 2 = 5 solve for x the

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first thing we are looking at is how to

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solve one-step equations you have to be

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good at solving one-step equations in

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order to pass any math test the idea of

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solving equations is to move everything

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with the X to the other side of the

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equation by performing the opposite

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operation on it we want only the X to be

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on one side of the equation so here we

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want to move the plus two to the other

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side of the equation we do that by

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performing the opposite operation on

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both sides of the equation the opposite

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operation of addition is subtraction the

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opposite operation of multiplication is

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division the opposite operation of

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exponent is the root or radical we know

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the opposite operation of addition is

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subtraction so we will subtract two from

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both sides once the opposite operation

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is done those two numbers simply cancels

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out so here the two will cancel out 5 -

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2 is 3 so X will be equal to 3 we have a

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free complete video on solving equations

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with a lot more

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examples please check it out with the

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link in the description for more let's

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move on to question

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two question 2 2x + 3 = 11 solve for x

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here we are looking at solving 2ep

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equations we said earlier that the whole

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idea of solving equations is to get get

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rid of everything and leave the X on one

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side of the equation for this question

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we will see that we have to get rid of

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the multiplication by 2 in the plus

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three 2x is the same as 2 * X when there

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are more than one operations we use the

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idea of the reversal of the order of

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operations to know which one to get rid

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of first so here is the order of

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operations if you are not familiar with

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the order of operations please revise

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our videos on it it's very important

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knowing the order of operations will

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make solving of equations super easy we

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can see that in the reversal of the

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order of operations that's from bottom

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to top we have addition before

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multiplication so we will get rid of the

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plus three first we get rid of the plus

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three by performing the opposite

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operation on it so we will subtract

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three from both sides the three will

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cancel out 11 - 3 is 8 so we have 2 x x

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= 8 next we will get rid of the

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multiplication by two by dividing both

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sides by two since division is the

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opposite of

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multiplication the two will cancel out 8

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/ 2 is 4 therefore x =

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4 question three 3x^2 + 8 = 20 solve for

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x we are looking at solving multi-step

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equations the process of solving is just

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like solving twostep equations we want

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to get the X on one side of the equation

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in order to do that we have to get rid

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of the multiplication by three the

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exponent 2 and the Plus 8 we will use

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the reversal of the order of operation

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to know which one to perform first let's

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bring our order of operations so here is

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our order of

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operations in the reversal we will

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notice that we have to to do the Plus 8

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first then we will do the multiplication

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by three and then we do the exponent two

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we will get rid of the Plus 8 by

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performing the opposite operation on it

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subtract eight from both sides the eight

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will cancel out 20 - 8 is 12 so now we

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have 3x^2 = 12 next we have to get rid

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of the multiplication by three we do the

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opposite operation we divide both sides

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by three

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the 3 will cancel out 12 / 3 is 4 so now

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we have x^2 = 4 we finally have to get

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rid of the exponent two we do the

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opposite operation the opposite

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operation of squared is square root we

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find the square root of both sides this

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will cancel out the square root of 4 is

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2 therefore x =

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2

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question 4 4x + 5 = 9 + 2x solve for x

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in our previous questions we have been

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having the X represented only once

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example 4x + 5 equals 9 but here we have

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the X represented twice in a case like

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this we want to move the X values to one

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side of the equation and work on it so

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here you can choose to move the 4X or 2X

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I'll move the 2x to the other side of

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the equation to do that since the 2x is

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adding you will subtract 2x from both

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sides of the equation the 2x will cancel

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out now 4x - 2x is 2x so we have 2X + 5

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= 9 we now have a familiar two-step

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equation which you should be able to

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solve if you've watched the previous

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questions but let's go over it we want

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to get rid of all the numbers at

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attached to the X so we can have the X

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alone on one side of the equation to

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achieve this we know that we must get

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rid of the time 2 in the + 5 let's bring

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our order of operations please you don't

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need to be writing the order of

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operations in your Solutions we are

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using it for teaching purpose we are

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using the reversal of the order of

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operations so we are working from the

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bottom up we will see that in this form

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we must do the addition first before the

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multiplication

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to get rid of the plus 5 we must perform

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the opposite operation on both sides of

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the equations so we will subtract five

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from both sides the five cancels out 9 -

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5 is 4 we now have 2x = 4 next we will

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get rid of the multiplication by two we

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do this by performing the opposite

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operation on both sides of the equation

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so we will divide both sides by two the

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two will cancel out 4 / 2 is 2 therefore

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x =

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2 question five the absolute value of x

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+ 3 = 7 find X for absolute value

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equations we equate the absolute value

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to the positive and negative of what is

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on the other side of the equation here

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we will equate the absolute value to

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positive and negative of the 7 so we

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have x + 3 = 7 and x + 3 = -7 we solve

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both equations for the first one we

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subtract three from both sides the three

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will cancel out 7 - 3 is 4 for the

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second one we subtract three from both

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sides the three will cancel out -7 - 3

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is -10 so our answer is x = 7 and and X

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=

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-10 question 6 the absolute value of x +

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1 + 6 = 9 find X in the previous

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question everything on the left side was

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in the absolute value Marks here the

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trick is that the plus 6 is not in the

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absolute value you need to remove

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everything that is not in the absolute

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value Mark and get only the absolute

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value on one side for you can equate to

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the negative and positive so we will

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first start by subtracting six from both

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sides the six will cancel out 9 - 6 is 3

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now we have the absolute value of x + 1

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= 3 we have only the absolute value on

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one side of the equation so we can

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equate x + 1 to the positive and

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negative of what is here as usual we

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have x + 1 = -3 and x + 1 = POS 3 we

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subtract one from all sides the one will

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cancel out for this one -3 - 1 will be

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-4 so x = -4 for this one 3 - 1 will be

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2 so x = 2 so x = -4 or x =

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2 question 7 s < TK x + 3 - 2 = 1 find X

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we are looking at radical

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equations a radical equation is an

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equation in which the variable is

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contained inside a radical or root sign

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here we see that the x is under the

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square root sign similar to what we did

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for absolute value equations we want the

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isolate the radical on one side of the

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equations we add two to both sides the

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two will cancel out 1 + 2 will give us

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three now we have the square < TK of x +

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3 = 3 next we want to eliminate the

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square root by squaring both sides of

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the equation for the left side the

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square root will cancel out the square

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we just get x + 3 3^ 2 is 9 we have a

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one-step equation we subtract three from

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both sides the three will cancel out 9 -

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3 is 6 therefore x =

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6

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question 8 4 / the quantity x - 5 = 3 /

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X find X we are looking at rational

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equations for rational equations we have

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the x or variable in the

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denominator the first step is to remove

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the fractions typically we will use the

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least common denominator method but for

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this question we can just cross multiply

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4 * X is 4 x 3 * x - 5 is 3 x - 15 we

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expanded it 3 * X is 3x and 3 * -5 is

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-15 next we want to isolate the X on one

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side of the equation we subtract 3x from

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both sides the 3x will cancel out 4x -

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3x is 1 X or simply X so we have X = -5

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as our answer

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question nine solve for x given that yal

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mx + b here we are looking at change of

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subject or transposing of

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formula this is the slope intercept form

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of the equation of a line when you are

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given any formula you should be able to

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find any of the

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variables this is nothing different from

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what we've been doing so far to solve

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for x we we want to have the X on one

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side of the equation and everything else

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on the other side of the equation to do

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that we have to move the times M and the

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plus b we will use the reversal of the

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order of operation to know which one to

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perform first let's bring our order of

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operations in the reversal we will

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notice that we have to do the plus b

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first then we will do the multiplication

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by m we will get rid of the plus b by

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performing the opposite operation on it

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subtract B from both sides the B will

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cancel out you cannot subtract y minus B

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because they are dissimilar as we

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learned in addition and subtractions in

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algebra so we will have y - B = MX next

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we have to get rid of the multiplication

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by m we do the opposite operation we

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divide both sides by m the m will cancel

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out there's nothing we can reduce on

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this other side so x = y - B all over

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M question 10 -3x + 1 is greater than 7

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solve for x here we are looking at

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solving inequalities the process is the

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same as solving

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equations there is a slight difference

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when you multiply or divide by a

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negative we want to get rid of

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everything and leave it X on one side of

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the inequality sign for this question we

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will see that we have to get rid of the

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multiplication by -3 and the plus one

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let's bring our order of

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operations we can see that in the

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reversal of the order of operations

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that's from bottom to top we have

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addition before

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multiplication so we will get rid of the

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plus first we get rid of the plus one by

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performing the opposite operation on it

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so we will subtract one from both sides

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the one will cancel out 7 - 1 is 6 so we

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have -3x is greater than 6 next we have

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to divide both sides by the -3 so we can

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get the X by itself in inequalities when

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you divide or multiply by negative the

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inequality changes so here the greater

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than becomes less than please take note

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of this nearly all wrong answers are

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because of this mistake

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now the -3 will cancel out 6 / -3 is -2

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therefore X is less than

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-2 question 11 solve the inequality -3

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less than x + 8 less than 20 here we are

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looking at combined

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inequalities this question is the same

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as -3 less than x + 8 and x + 8 less

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than 20 we just com combine them the

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solution is exactly the same instead of

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having two sides you now have three

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sides to get the X by itself we have to

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subtract eight from all three sides the8

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will cancel out here -3 - 8 is

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-11 then 20 - 8 is 12 so our answer is

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-1 less than x less than 12 question 12

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graph the inequality X greater than

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-4 here we are looking at graphing

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inequalities let's bring our number line

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when graphing inequalities the first

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thing is to locate your point which will

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be the number here it is -4 then you'll

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draw a shaded or unshaded circle at the

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point if you have less than or greater

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than then the circle will not be shaded

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if you have less than or equal to or

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greater than or equal to you will use

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the Shaded Circle

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so basically if it has an equal to you

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will shade in this case since it's just

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greater than we will not shade the

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circle then finally we draw an arrow the

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easiest way to get this always right

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without thinking is to make sure your

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inequality is in the form variable

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inequality sign and then the number in

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that form the direction of your arrow

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will be the same as the direction of the

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inequality sign here since this is in

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that form we will draw our Arrow facing

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here and we are

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done question 13 in order to ship 2,500

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gallons of a product to another country

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Stan shipping company had to package the

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gallons into boxes if they had 20

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package boxes and 100 gallons left that

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are not in boxes how many gallons were

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in a box this kind of two-step equation

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word problem is is very common we are

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first going to solve it in details for

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teaching purpose then I'll show you how

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you can solve it in less than 10 seconds

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on an actual test you have three values

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in these type of questions let's write

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them down we have 2,500 gallons we have

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20 boxes and finally we have 100 gallons

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the 2,500 gallons represents the total

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so we have equal

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2,500 the 20 box is what I call the

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group The gallons have been grouped into

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boxes for most questions the group can

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also be identified as the number that

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represents something different from the

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other two numbers so here 2,500

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represents gallons the 100 also

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represent gallons but the 20 represent

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boxes so the 20 will be the group the

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group is the one with the X so we will

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have

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20x we can now add the 100 gallons left

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to to the equation and solve for the X

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in this two-step equation subtract 100

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from both sides these will cancel out

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2500 - 100 will be

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2,400 we now have 20x =

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2,400 divide both sides by 20 the 20

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will cancel out 2,400 ided 20 will be

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120 this means there were 120 gallons in

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each box the hard part of this question

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is to be able to pull out the values

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from the word

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problem we went through a detailed

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solution for teaching purpose let's look

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at how you can speed up solving this

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question first there's absolutely no

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reason to write this part if you know

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what you're doing you can go straight to

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writing your two-step equations we have

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our group 20x our other

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+ and our total

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2,500 then you can solve the two-step

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equation

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equation an even faster method to solve

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this question in less than 10 seconds is

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to do 2,500 minus 100 divided by 20 on

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your calculator to get

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120 we did the total minus other divided

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by the group a big caution when using

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fast methods is to note that they are

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very specific to specific questions and

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little twists to the question can let

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you get it wrong so when in doubt use

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the longer

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methods

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question 14 five added to Thrice

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Michael's age is 50 how old is Michael

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for question like this it is good

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practice to start with identifying your

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unknown value and representing it by a

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letter let's say x the unknown value is

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usually what the question is asking you

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to find here it is Michael's age let's

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represent it with X now we just

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translate we know added to is addition

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Thrice is three times so Thrice

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Michael's age is 3x and is means equal

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to so this is 5 + 3x = 50 you can now

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solve the two-step equation we subtract

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five from both sides the five will

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cancel out 15 - 5 will be

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45 so we have 3x =

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45 next we will divide both sides by

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three this will cancel out 4 5 / 3 is 15

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therefore x = 15 Michael's age is 15

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years question 15 which of the relations

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below is not a function to answer this

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question let's go through a few things

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about functions when you have a notation

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example 25 the two represents the input

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value that's x value the five represents

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the output value that's the Y value this

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is the same as what we will learn in

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graphing points for a relation to be a

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function no input value can have

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multiple output values also all input

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values must have output values let's

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look at examples here the input values

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are these and the output values are

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these note that each input value

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corresponds to only one output value

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although three is an output value

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without any input value corresponding to

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it it is still a function this could

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have been written in this form we wrote

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each of the input values and what output

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value they correspond to now let's look

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at this relations this relation is not a

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function because the input two has more

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than one output value that's seven and

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five no input value can have more than

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one output value this could have been

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written this way notice we have two

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written twice with different y values

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one is seven and the other is five

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finally let's look at this

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relations this is a function multiple

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input values can go to the same output

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value so here although the input value

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four and the input value five both gives

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eight it is a function again this could

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have been written this way notice we

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have our y value 8 written twice with

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this information let's answer answer our

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question the answer is c c is not a

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function the input value three has two

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output values that's six and8 for a

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function no input value can have more

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than one output

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values Happy Thanksgiving get the full

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course at ultimate algebra.com and

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change your algebra forever watch more

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