Calculate the molar solubility of CuOH2 Ksp 48x1020 and Kfor

Calculate the molar solubility of Cu(OH)2, Ksp= 4.8x10-20 and Kform= 1.1x1013, in 2.0 M NH3. (For simplicity, ignore the reaction of NH3 as a base.) HELP!!

Cu(OH)2=Cu2+ +2OH- Ksp= 4.8*10^-20
Cu2+ + 4NH3=Cu(NH3)2 2+ K=1.1*10^13

Cu(OH)2+4NH3=Cu(NH3)4 2+ +2OH-

K= Ksp*K=4.8*10^-20 * 1.1*10^13=5.28e-7
I ----- 1 M 0 0
C ----- -4x +x +2x
E ------ (2-4x) x 2x
K=(x*(2x)^2)/(2-4x)^4
5.28e-7=4x^3/(2-4x)^4

x=0.012 mol/L