Question

Which is the area of a circle with a circumference of 15.7 units (use 3.14 for pie

Answer 1

c=2pir
15.7=2pir
divide by 2
7.85=pir
divide both sidse by pi
7.85/pi=r

ok so
area=pir^2
area=pi(7.85/pi)^2
area=pi(61.6225/(pi^2))
area=61.6225/pi
use 3.14 for pi
area=61.6225/3.14
area=19.625 square units