4a-12b=4(a-3b);
-15x-25y=-5(3x+5y)
13a-13=13(a-1)
4x3+2=2(2x3+1)
P(2+a)-3(a+2)= (a+2)(p-3)
K(x+y)2-p(x+y)= (x+y)((x+y)-p)
(X-y)2-p(y-x)=(x-y)(x-y-p)
A(p-k)+b(k-p)2= (k-p)(b(k-p)-a)
4(a-b)+3(b-a)2= (b-a)(3(b-a)-4)
7(x-y)2-(x-y)3=(x-y)2(7-(x-y))
9y3(p-2)-3y2(p-2)=3y2(p-2)(3y-1)
3x4(1-y)-6x3(y-1)=3x3(1-y)(x+2)