Question

Find the exact circumference of a circle with an area equal to 36pi sq. in.

a. 12pi
b. 18pi
c. 324pi

Answer 1

12 pi. So the equation for area is pi(r)squared so you have to set pi(r)squared equal to 36 and solve for "r". R is equal to six. After, you use "r" in the circumference formula which is 2(pi)r which would be 2(pi)6 which equals to 12pi

Answer 2

The correct option is:

a. 12π

Explanation:

We are given Area of circle= 36π sq. in.

We have to find the circumference of the circle.

Let r be the radius of the circle.

Then, area=πr²

i.e. πr²=36π

⇒ r²=36

⇒ r=6 in.

Hence, circumference= 2πr

=2×6×π

= 12π

Hence, the correct option is:

a. 12π