Question

In a circle, a 90 degree sector has area of 64pi ftsqd. what is the radius of the circle?

Answer 1

if a circle has 360 degrees, 90 degrees is one forth of it

Answer 2

so the total area is 4 times 64pi or 256 pi

Answer 3

A=pi times r^2
256pi=(pi)r^2
256=r^2
r=16