Rational expressions question.

This problem is confusing me somewhat, so I would really appreciate any help. I know that the final answer is 3x.

(3-x)^2 x + (3-x)x^2
________________
x-3

note: in the numerator, on the left hand side, the power of 2 is not attached to the x. The x is just on its own. the power of 2 just applies to the terms in the bracket.

thanks in advance.

(3-x)^2 x + (3-x)x^2
________________ =

(x-3)^2 x -(x-3)x^2
________________
(x-3)

= (x-3)x - x^2 = x^2 - 3x - x^2 = -3x is the answer and not 3x

numerator = (3-x)[(3-x)x+x^2]
=(3-x)[3x-x^2+x^2]
=(3-x)(3x) = -3x(x-3)
denominator = (x-3)
-3x(x-3)/(x-3) = -3x