已知多项式25x^2-10xy+y^2+10x-2y-3的值为0,求5x-y的值

问题描述:

已知多项式25x^2-10xy+y^2+10x-2y-3的值为0,求5x-y的值

25x^2-10xy+y^2+10x-2y-3=0
(5x-y)²+2(5x-y)-3=0
(5x-y-1)(5x-y+3)=0
5x-y-1=0或5x-y+3=0
得5x-y=1或5x-y=-3