equation of circle = (x-h)^2 + (y-k)^2 = r^2
r is the radius and (h,k) is the center of the circle. we are given (h,k) and just need to find r^2
The length of the radius (r) would be the distance between the center and the point it passes through.
r^2 would be the square of that distance
Find the square of the distance between (-1,6) and (-6,1) using the distance formula
d^2 = (1-6)^2 + (-6--1)^2 = 50
Now plug values into equation.
