I have not had Math in 4 years! Can somone please show me how to do this problem:

The equation of a circle is 4x^2+4y^2+32x-32y+92=0

a. Finde the center (h,k) of the circle (50%)

b. Find the radius r of the circle (50%)

a: (h,k) =

b: r=

Thank You So Much!