Please write that x^2 + y^2 = 7^2. The " ^ " indicates exponentiation.
This is the equation of a circle with center at the origin and radius 7.
Supposing that you translate this circle's center to point (h,k). The equation is then
(x-h)^2 + (y-k)^2 = 7^2. The new center is (h,k) = (-3, 2). Substitute -3 for h and 2 for k in the above equation.
Simplify your result and you'll then be done!