3x-4y+2xy)--(2x--5y+5xy)=当x+y=5,xy=-3
[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-
3x-4y+2xy)--(2x--5y+5xy)=当x+y=5,xy=-3
已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2
已知x+y分之xy=2,那么3x-5xy+3y分之3xy-x-y=
已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y=
已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值
已知xy/x+y=3,求代数式2x-5xy+2y/x-3xy+y
已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值
已知X+Y分之XY=2,求-X+3XY-Y分之3X+5XY+3Y
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.