x^2*(x-6)^2+14(x-3)^2=81
x-3=t
((t+3)*(t-3))^2+14t^2-81=0
(t^2-9)^2+14t^2-81=0
t^4-4t^2=0
t=0 x=3
t=2 x=5
t=-2 x=1
