Answer:
A. 8
Step-by-step explanation:
When finding the radius of a circle given area we have to remember the following formulas
[tex]A=\pi *r^{2}[/tex] and [tex]r^2=\frac{A}{\pi }[/tex] or [tex]r=\sqrt{\frac{A}{\pi } }[/tex]
So using either [tex]r^2=\frac{A}{\pi }[/tex] or [tex]r=\sqrt{\frac{A}{\pi } }[/tex] we fill out the following
[tex]r^2=\frac{64\pi }{\pi }[/tex] [tex]r=\sqrt{\frac{64\pi }{\pi } }[/tex] both would equal 8
The image below explains how we get 8
