Write the equation of a circle that has a center of (-8,-11) and a radius of 4.

Answer 1

(x+8)^2 + (y+11)^2 = 4^2

(x+8)^2 + (y+11)^2 = 16

or

x^2 +16x + 64 + y^2 + 22y + 121 = 16

x^2 +16x + y^2 + 22y = -169

general form of the equation is (x-h)^2 + (y-k)^2 = r^2 where (h,k) is the center of the circle and r = radius of the circle.