6x^2+2x-5xy-6y^2+23y-20
=6x^2-5xy-6y^2+2x+23y-20
=(3x+2y)(2x-3y)+2x+23y-20
=(3x+2y-5)(2x-3y+4)
6x^2+2x-5xy-6y^2+23y-20用十字相乘分解因式
6x^2+2x-5xy-6y^2+23y-20
=6x^2-5xy-6y^2+2x+23y-20
=(3x+2y)(2x-3y)+2x+23y-20
=(3x+2y-5)(2x-3y+4)