已知X=2.5,Y=1,求分式-X²+8XY-15Y²/X²-3XY-10Y²的值

问题描述:

已知X=2.5,Y=1,求分式-X²+8XY-15Y²/X²-3XY-10Y²的值
谢谢

原式=-(x-3y)(x-5y)/(x-5y)(x+2y)=-(x-3y)/(x+2y)=-1/9