2x+2y=6 3x-5y=25 求xy

√x(√x+2√y)=√y(6√x+5√y,求x-3√xy+2y/x+√xy-6y ∫x(∫x+2∫y)=∫y(6∫x+5∫y),求：（x+∫xy-y)/(2x+∫xy+3y) 已知xy=-2,x-y=3,求（x+y)（x-y)-y^2+（x-y)^2-（6x^2y-2xy^2)÷2y 若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+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xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值 已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值 已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy 已知xy/(x+y)=2求(3x-5y+3y)/(-x+3xy-y)