Answer
$(x-3)^2+(y-8)^2=169$
Work Step by Step
Center: $(h,k)=(3,8)$
The distance from the center to the solution point is the radius:
$$r=\sqrt {[3-(-9)]^2+(8-13)^2}=\sqrt {144+25}=\sqrt {169}=13$$
The standard form of the equation of a circle with center at $(h,k)$ and radius $r$ is:
$$(x−h)^2+(y−k)^2=r^2$$ Substituting the values:
$$(x-3)^2+(y-8)^2=13^2$$ Simplifying:
$$(x-3)^2+(y-8)^2=169$$
