a) x(x-y)+(x-y)=(x+1)(x-y)
b) 2x+2y -x(x+y)= 2(x+y)-x(x+y)=(2-x)(x+y)
c)\(\left(2x+3\right)^2+2\left(2x+3\right)=\left(2x+3\right)\left(2x+2+3\right)=\left(2x+3\right)\left(2x+5\right)\)
d)\(\left(x-2\right)\left(x-1\right)-4\left(x-2\right)=\left(x-2\right)\left(x-1-4\right)=\left(x-2\right)\left(x-5\right)\)
e)\(x+y-x^2y-xy^2=\left(x-x^2y\right)+\left(y-xy^2\right)=x\left(1-xy\right)+y\left(1-xy\right)\)
\(=\left(x+y\right)\left(1-xy\right)\)
g, = (x+2y)(4x+3)
h, = (2x+1)(10-3x)
i, = xy(x+1)[(xy+1)+2]
j, = (2-z)(x2+y2-1)
k, = 2(x+3)2
f = 5(x-y)(x-2)