已知2x=3y,求xy/xx+yy-yy/xx-yy的值

已知2x=3y,求xy/xx+yy-yy/xx-yy的值 已知x(x-1)-(xx-y)=-3求xx+yy-2xy 已知x（x+1)-(xx+y)=3,求(xx+yy)/2-xy的值 已知xx+yy+4x-6y+13=0,求（xx-2x）/xx+3yy的值. x,+y=5 xy=3 求xx+yy x(x+1)-(xx+y)=-3,求(xx+yy)/2-xy的值 已知（XX+YY—2）（XX+YY）=3,求XX+YY xx+2xy+yy=1 xx-2xy+yy=49 求xx+yy,xy. 已知xx+yy=7,xy=-2,求多项式5xx-3xy-4yy-11xy-7xx+2yy的值. 已知XX—XY=5,XY—YY=-3,求代数式XX—YY和XX—2XY+YY 已知xy+yy=3,xx+xy=-1/2,求2xx+3xy+yy的值 若xx+yy-2x-6y+10=0,求分式（xx-yy）/xy的值. 已知14(XX+YY+ZZ)=(X+2Y+3Z)^2,求X:Y:Z x-y=3,(x+y)(x+y)=25,求xy/xx+yy的值? 已知x,y是实数,且适合方程(xx+xy-12)(xx+xy-12)+(xy-2yy-1)(xy-2yy-1)=0求x,y的值 已知x+y=7,xy=-8,求xx+yy xx+2x+yy+6y+10=0求xx+yy的值 已知（x-2）2+1y-31=0,求xx+yy-xy-yx的值.