6x²-xy-15y²=0 求x²-2xy+4y²/2x²-3xy-3y²
问题描述:
6x²-xy-15y²=0 求x²-2xy+4y²/2x²-3xy-3y²
告诉下
答
6x²-xy-15y²=0
(2x+3y)(3x-5y)=0
2x+3y=0,3x-5y=0
x=-3y/2,x=5y/3
代入原式
x=-3y/2
原式=(37y²/4)/(6y²)=37/24
x=5y/3
原式=(31y²/9)/(-22y²/9)=-31/22