Work Shown:
The area is 144pi square feet. So A = 144pi is plugged into the formula below to isolate r
A = pi*r^2
144pi = pi*r^2
144 = r^2 .... divide both sides by pi, the pi terms cancel
r^2 = 144
r = sqrt(144) ... take the square root of both sides
r = 12
This is plugged into the circumference of a circle formula
C = 2*pi*r
C = 2*pi*12
C = 2*12*pi
C = 24pi
This is approximately equal to 75.36 when you use the approximation pi = 3.14
