已知5x*x-xy-6y*y=0,求xy的比值
已知x>0,y>0,且x+6y=5根号xy,求(2x+根号xy-y)分之(x+根号xy+2y)的值
已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.
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.
已知y=3xy+x,求代数式2x+5xy-2y/x-2xy-y的值(xy≠0)
已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值
已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值
已知y-x-2xy=0,求3x+xy-3y/y-xy-x的值
已知y-x-2xy=0,求(3x+xy-3y)\(y-xy-x)的值
已知xy/x+y=6,求3x-2xy+3y/-x+3xy-y的值.
已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值