Question

The area of a circle is 9π m². What is the circumference, in meters? Express answer in terms of π

Answer 1

20.25 pi

Explanation:

The circumference of a circle is given by

C = 2 * pi *r

9 pi = 2 * pi *r

Divide each side by 2pi

9pi / 2 pi = 2 pi r / 2 pi

4.5 = r

Now we can find area

A = pi r^2

= pi ( 4.5)^2

20.25 pi