#### Answer

$64\pi$ square feet

#### Work Step by Step

We are given that $A(r)=\pi r^{2}$. This relation is written in function notation, which tells us that the area of a circle is a function of its radius. Therefore, if we know the radius of a circle, we can calculate the area of that circle.
We are given that the radius is 8 feet. We can insert $r=8$ into the equation to find the area of the circular garden.
$A(8)=\pi 8^{2}=\pi \times8\times8=64\pi$ square feet