Question

Find the exact area of a circle having the given circumference.

8 pi
A =

a)4√2 pi
b)16 pi
c)64 pi

Answer 1

Answer is B

Explanation:

The formula for the area is: A=\pi r^2

A=\pi (4)^2\\A=16\pi

Answer 2

Answer: B

Explanation:

`C=8\pi`

`C=2\pi r`

Solve for r.

`r=(C)/(2\pi)`

`r=(8\pi)/(2\pi) \\r=4`

The formula for the area is:
`A=\pi r^2`

`A=\pi (4)^2\\A=16\pi`