ÁREA DE FIGURAS PLANAS | RESUMO | GEOMETRIA PLANA |

Summary

This video provides a concise overview of calculating areas for various flat shapes, commonly tested in exams like the ENEM and vestibular. It covers essential formulas for squares, rectangles, triangles (including equilateral), parallelograms, rhombuses, trapezoids, and circles, explaining each one with simple, clear examples. The video also emphasizes key tips, such as the importance of using the correct perpendicular height and distinguishing between radius and diameter in circles. Additionally, it directs viewers to further resources for detailed exercises and applications. Perfect for anyone seeking a quick refresher before exams.

Takeaways

• 😀 The area of a square is calculated by squaring the side length: A = l².
• 😀 The area of a rectangle is determined by multiplying the base by the height: A = b × h.
• 😀 For a triangle, the area is calculated by the formula: A = (b × h) / 2.
• 😀 In the case of an equilateral triangle, the area formula is A = (l² × √3) / 4, where l is the length of the sides.
• 😀 A parallelogram's area is calculated the same way as a rectangle: A = b × h, where the height is perpendicular to the base.
• 😀 The area of a rhombus is calculated as A = (d₁ × d₂) / 2, where d₁ and d₂ are the lengths of the diagonals.
• 😀 A trapezoid’s area is determined by A = ((b₁ + b₂) × h) / 2, where b₁ and b₂ are the lengths of the two bases and h is the height.
• 😀 The area of a circle is calculated using A = π × r², where r is the radius of the circle.
• 😀 Don't confuse the radius (r) with the diameter, as the diameter is twice the radius.
• 😀 This video is a quick refresher on the most common area formulas, with links provided for further detailed explanations and exercises.

Q & A

What is the formula for calculating the area of a square?

The area of a square is calculated by squaring the length of one side: A = l^2, where l is the length of a side.

How do you calculate the area of a rectangle?

The area of a rectangle is calculated by multiplying the base (b) by the height (h): A = b × h.

How is the area of a triangle calculated?

The area of a triangle is calculated by multiplying the base (b) by the height (h) and dividing by two: A = (b × h) / 2.

What is the formula for the area of an equilateral triangle?

The area of an equilateral triangle is given by A = (l^2 × √3) / 4, where l is the length of a side.

How do you calculate the area of a parallelogram?

The area of a parallelogram is calculated by multiplying the base (b) by the height (h): A = b × h, where the height is perpendicular to the base.

What is the formula for the area of a rhombus?

The area of a rhombus is calculated by multiplying the lengths of the diagonals (D and d) and dividing by two: A = (D × d) / 2.

How do you calculate the area of a trapezoid?

The area of a trapezoid is calculated by adding the lengths of the two bases (B and b), multiplying by the height (h), and dividing by two: A = ((B + b) × h) / 2.

What is the difference between the radius and the diameter of a circle?

The radius (r) is the distance from the center of the circle to any point on its edge. The diameter (d) is the distance across the circle, passing through its center, and is twice the length of the radius.

What is the formula for the area of a circle?

The area of a circle is calculated using the formula A = π × r^2, where r is the radius.

What should you remember when calculating the area of a parallelogram?

You must always use the height that is perpendicular to the base when calculating the area of a parallelogram. Avoid using the slanted side.