x²-xy+3y-3x
=x(x-y)-3(x-y)
=(x-y)(x-3)
2x²+xy-y²-4x+5y-6
=(2x-y)(x+y)-4x+5y-6
=(2x-y+2)(x+y-3)第二题能不能解答过程再详细一些！拜托了，完成给你2x²+xy-y²-4x+5y-6=(2x-y)(x+y)-4x+5y-6=(2x-y+2)(x+y-3)就是两个十字相乘法：2x -y ╳x y 2x-y2 ╳x+y 3