若1/x-1/y=3,则(5x 3xy-5y)/(3x-xy-3y)=?(要用到‘分子分母同乘或同除一个数’的值不变)Thanks a lot是（5x+3xy-5y）/（3x-xy-3y）

若x-y=4,xy=1,则(2x+y-2xy)-(3x+2y+xy)-(4xy+3y-5x)= 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 若1/x+1/y=2,则(2x-xy+2y)÷(3x+5xy+3y) 若1/x-1/y=2,求3x-2xy-3y/x-xy-y的值3x-2xy-3y/x-xy-y 不好意思，是3x-2xy-3y/x-2xy-y 若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( ） 若实数x,y满足1/x-1/y=5,则分式3x-2xy-3y/x+xy-y的值等于? 若1/x-1/y=3,5x+3xy-5y/3x-xy-3y 已知1/x-1/y=-3,则x+5xy-y/3x-2xy-3y= 若1/x+1/y=5,求3x+4xy+3y/x+3xy+y的值 若1/x-1/y=2,则（3x+xy-3y)/(x-xy-y）的值为? 已知1/x-1/y=3,则(5x+xy-5y)/(x-xy-y) =9= 已知1/x=3+1/y,则(2x-5xy-2y)/(y+3xy-x)=_______. 若1/X-1/Y=3,则2X+XY-2Y/X-2XY-Y=? 已知1/X-1/Y=3 则(5X+XY-5Y)/(X-XY-Y)=? 若1/X-1/Y=3,求5X+2XY-5Y/X-4XY-Y 若1/x-1/y=3,求5x+2xy-5y/x-4xy-y的值 已知1/x-1/y=3,则5x+xy-5y/x-xy-y等于 已知1/x-1/y=3,则5x+xy-5y/x-xy-y的值为?