(2x - 6)2 = 2*(x-3)*2*(x-3) =4*(x-3)2
(5y + 5)2 = 5*(y +1) *5*(y+1) = 25*(y+1)2
(36x +30y)2 = 6*(6x +5y)*6*(6x+5y) = 36*(6x +5y)2
(2x +4)4 = 2*(x + 2)*2*(x + 2)*2*(x +2)*2*(x + 2) = 16*(x +2)4
(6x-9y)3 = 3*(2x-3y)*3*(2x - 3y)*3*(2x-3y) = 27*(2x - 3y)3
(a2 + ab)2 = a*(a +b)*a*(a + b) = a2*(a + b)
(-7a -14ab)2 = -7a*(1 +2b)*(-7a)*(1 + 2b) = 49a2*(1 + 2b)2
(3c4 -6c3)4 = 3c3*(c -2)*3c3*(c-2)*3c3*(c-2)*3c3*(c-2) = 81c7(c-2)4