(Vì hơi dài nên mình làm hơi lâu, bạn thông cảm ha :>)
\(1, -a-b+x\left(a+b\right)=-\left(a+b\right)+x\left(a+b\right)=\left(a+b\right)\left(-1+x\right)\)
\(2, ax+ay+bx+by=a\left(x+y\right)+b\left(x+y\right)=\left(a+b\right)\left(x+y\right)\)
\(3, ax+ay+2x+2y=a\left(x+y\right)+2\left(x+y\right)=\left(a+2\right)\left(x+y\right)\)
\(4, ax+ay-bx-by=a\left(x+y\right)-b\left(x+y\right)=\left(a-b\right)\left(x+y\right)\)
\(5, ax+ay-2x-2y=a\left(x+y\right)-2\left(x+y\right)=\left(a-2\right)\left(x+y\right)\)
\(6, -2x-2y+ax+ay=-2\left(x+y\right)+a\left(x+y\right)=\left(-2+a\right)\left(x+y\right)\)
\(7, x^2+xy-2x-2y=x\left(x+y\right)-2\left(x+y\right)=\left(x-2\right)\left(x+y\right)\)
\(8, x^2-xy-2x+2y=x\left(x-y\right)-2\left(x-y\right)=\left(x-2\right)\left(x-y\right)\)
\(9, x^2-xy+2x-2y=x\left(x-y\right)+2\left(x-y\right)=\left(x+2\right)\left(x-y\right)\)
\(10, 10ax-5ax-5ay+2x-y=\) (Mình thấy câu này nó cứ sao sao á)
