3(x-y）/5(y-x)=-3/5
(x-y)/(y-x)=-1
(x-y)/(y-x)+1=0
(x-y+y-x)/(y-x)=0
0/y-x=0
因为分母不为0,所以x不等于y分式5/x-y+3/(x-y)^2怎么解?