x+7/xy+3=5 求y

求（3x^+y^-5xy）-【2x^-（-4xy-y^+7x^）】=? 求（3x^+y^-5xy）-【2x^-（-4xy-y^+7x^）】=? 已知xy^2=-2求xy（2x^3y^7+5x^2y x-y=3,xy=5,求代数式（7xy+4x-7y）+(6x-3xy)-(3y+4xy)的值快 已知X+Y=6,xy=3求代数式（5XY+4X+7Y)+(6X-3XY)-(4XY-3Y)的值 已知x+y=3,xy=1,求代数式5xy+4x+7y+6x-3xy-4xy+3y的值. x+y=8,xy=-2,求(5xy+4x+7y)+(6x-3xy)-(4xy-3y)的值 已知xy平方=-2,求-xy(x^3y^7-3x^3y^7-y)刚刚发现打错题了，应该是：已知xy平方=-2,求-xy(x^3y^7-3x^2y^5-y) xy^2=-3,求-xy(x^2y^5-xy^3-y) 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xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值.已知xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值. 已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2 已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值 x+7/xy+3=5 求y 已知xy^2=-2求xy（2x^3y^7+5x^2y^5-y)的值 已知xy^2=-6,求-xy(x^3y^7-3x^2y^5-y）的值 已知xy^2=-2,求-xy(x^3y^7-3x^2y^5-y)的值