Question

A circle has an area of 441π cm2. What is the circumference?
a.21π cm
b.42π cm
c.42 cm
d.21 cm

Answer 1

A=pi*r^2
C=2*pi*r

Answer 2

Yeah I know but I dont know how to get the circumference from the area

Answer 3

...

Answer 4

since you have the area of a circle, then you can find the radius of the circle

once you determine the radius of the circle, you can then use it to calculate the circumference of the circle

Answer 5

okay so 441= 3.14r^2