已知xy^2=-3,求-xy（x^3x^2y^5-y）的值 打错了，是求-xy（x^3y^7=3x^2y^5-y)

已知x:y=3:2,求(x²+3xy)/(xy+2xy) 已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2 已知（x+1）*（x+1）=-Iy-1I,求2（xy-（5xy）*（5xy））-3（（xy）*（xy）-xy） 已知xy为正整数,3xy=2x+3y+5.求xy=? 已知xy^2=-2,求-xy（x^2y^5-xy^3-y)的值. 已知xy^2=-2 求-xy(x^2y^5-xy^3-y) 已知(x+1)²+|y-1|=0,求2(xy-5xy²)-(3xy²-xy)得值 已知X+Y=3XY,求2X+2Y-XY除以X+Y+2XY的值,要算理.已知X+Y=3XY,求2X+2Y-XY除以X+Y+2XY的值,要算理. 已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy 已知xy/x+y=3,求2x-3xy+2y/-x+3xy-y的值 已知xy/x+y=3,求2x-3xy+2y/-x+3xy-y的值 已知x-y=3xy,求分式3x+2xy-3y/x-2xy-y的值 已知xy/(x+y)=3,求(2x-3xy+2)/(3xy-x-y)的值 已知xy/x+y=2,求代数式3x-xy+3y/-x+3xy-y的值 已知xy/x+y=6,求3x-2xy+3y/-x+3xy-y的值. 已知(xy)/(x+y)=6求(3x-2xy+3y)/(-x+3xy-y)的值. 已知X+Y分之XY=2,求-X+3XY-Y分之3X+5XY+3Y 已知y=3xy+x,求代数式2x+3xy-2y/x-2xy-y的值