Question

What is the exact area of a circle with a circumference of 18 times pi centimeters

Answer 1

First, find the radius

2$\pi$r=circumference
r=18 $\pi$ cm
-------------
2$\pi$
r=9 cm

Now, we can just use the circle area formula to solve

$\pi$$r^{2}$
=$\pi$ $9^{2}$
=81 $\pi$ 
=254.469 cm^2