Use the fact that (x-h)² + (y-k)² = r² is the equation of a circle, where (h,k) = the center and r = the radius. In your problem, x² + (y+2)² = 25, write x as (x-0) and 25 as 5² (x-0)² + (y+2)² = 5² Compare that to (x-h)² + (y-k)² = r² and we see that h=0, k=-2, and r=5 so the center is (0,-2) and the radius is 5. Edwin