1/(x+y)-1/(x-y)=-3/20,2/(x+y)+3/(y-x)=-(1/5)急啊!
问题描述:
1/(x+y)-1/(x-y)=-3/20,2/(x+y)+3/(y-x)=-(1/5)急啊!
答
1/(x+y)-1/(x-y)=-3/20 ---(1) 2/(x+y)+3/(y-x)=-(1/5) --- (2)
(1)式x2 -(2)式得出 X-Y=2,即 X=2+Y (3)
将(3)式 代入(1)式中,得出 Y=3/7
即可得出X=17/7