Circumference, Area, Composite Figures Review

Front

What is the formula for the area of a circle?

Back

Area = πr², where r is the radius of the circle.

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr, where r is the radius of the circle.

Front

How do you find the area of a semicircle?

Back

Area = (πr²) / 2, where r is the radius of the semicircle.

Front

What is a composite figure?

Back

A composite figure is a shape that is made up of two or more simple shapes.

Front

How do you find the area of a composite figure?

Back

Find the area of each simple shape and then add them together.

Front

What is the diameter of a circle?

Back

The diameter is twice the radius of the circle.

Front

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

Back

Area = π(7)² = 154 cm² (approximately).

Front

If the radius of a circle is 10 ft, what is the circumference?

Back

Circumference = 2π(10) = 62.83 ft (approximately).

Front

What is the area of a circle with a radius of 5 cm?

Back

Area = π(5)² = 78.54 cm² (approximately).

Front

What is the last step to find the area of a semicircle?

Back

Divide the area of the circle by 2 to find the area of the semicircle.