Area of Circles and Triangles

Front

What is the formula for the area of a circle?

Back

The area of a circle is calculated using the formula A = πr², where A is the area and r is the radius.

Front

What is the formula for the area of a triangle?

Back

The area of a triangle is calculated using the formula A = 1/2 * base * height.

Front

If the radius of a circle is 7 inches, what is its area?

Back

A = π(7)² ≈ 153.94 in².

Front

If the base of a triangle is 10 cm and the height is 5 cm, what is its area?

Back

A = 1/2 * 10 * 5 = 25 cm².

Front

What does π (pi) represent in the area of a circle?

Back

π (pi) is a constant approximately equal to 3.14, used in calculations involving circles.

Front

How do you find the radius if you know the area of a circle?

Back

To find the radius, use the formula r = √(A/π), where A is the area.

Front

What is the area of a circle with a diameter of 10 inches?

Back

First, find the radius: r = diameter/2 = 5 inches. Then, A = π(5)² ≈ 78.54 in².

Front

What is the area of a triangle with a base of 8 m and a height of 3 m?

Back

A = 1/2 * 8 * 3 = 12 m².

Front

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

Back

The diameter is twice the radius: diameter = 2 * radius.

Front

If a circle has an area of 314.16 in², what is its radius?

Back

r = √(314.16/π) ≈ 10 in.