Question 1052458
The goal is to factor each piece. Then simplify by canceling common terms. 



{{{(3x-x^2)/(x^2-9)}}}



{{{(-x(x-3))/(x^2-9)}}}



{{{(-x(x-3))/((x-3)(x+3))}}} Difference of squares rule



{{{(-x*highlight((x-3)))/(highlight((x-3))(x+3))}}}



{{{(-x*cross((x-3)))/(cross((x-3))(x+3))}}}



{{{(-x)/(x+3)}}}



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{{{(3x-x^2)/(x^2-9)}}} simplifies to {{{(-x)/(x+3)}}}