Question 639844
{{{x^2 -y^2 +x -y}}}


{{{(x^2 -y^2) +(x -y)}}}


{{{(x+y)(x-y) +1(x -y)}}}


{{{(x+y+1)(x-y)}}}


{{{(x-y)(x+y+1)}}}



So the answer is {{{(x-y)(x+y+1)}}}