## College Algebra (6th Edition)

$x^{2}+y^{2}=64$
We know that the standard form of the equation of a circle with center $(h,k)$ and radius $r$ is $(x-h)^{2}+(y-k)^{2}=r^{2}$. Therefore, we can plug in the given values for $h$, $k$, and $r$ and simplify. $(x-0)^{2}+(y-0)^{2}=(8)^{2}$ $x^{2}+y^{2}=64$