Answer
The radius of the circle is $6$ inches.
Work Step by Step
Let the side length of the square is $=a$.
Area of the square $A=36\pi$ square inches.
Area formula for the circle is
$\Rightarrow A=\pi r^2$
Substitute $36\pi$ for $A$.
$\Rightarrow 36\pi=\pi r^2$
Divide each side by $\pi$.
$\Rightarrow 36=r^2$
Use $36=6^2$.
$\Rightarrow 6^2=r^2$
Take square root on each side.
$\Rightarrow 6=r$
Hence, the radius of the circle is $6$ inches.
