Answer
$(x+1)^{2}+(y+4)^{2}=64$
Work Step by Step
Center $(-1,-4);$ radius $8$
The equation of a circle is $(x-h)^{2}+(y-k)^{2}=r^{2}$, where $(h,k)$ is the center of the circle and $r$ is its radius.
Both the center and the radius of the circle are given. Substitute them into the formula to obtain its equation:
$(x-h)^{2}+(y-k)^{2}=r^{2}$
$[x-(-1)]^{2}+[y-(-4)]^{2}=(8)^{2}$
$(x+1)^{2}+(y+4)^{2}=64$