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:
$r=\sqrt {[3-(-9)]^2+(8-13)^2}=\sqrt {144+25}=\sqrt {169}=13$
Equation of a circle:
$(x−h)^2+(y−k)^2=r^2$ (standard form)
$(x-3)^2+(y-8)^2=13^2$
$(x-3)^2+(y-8)^2=169$
