x+y/x-y=5/2,求x/y的值

若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1/y)]/[(x+1)/y]的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 y=3(x-y),x=2(x-y)求x,y的值 已知x≠y,x^2-x=y^2-y,求x+y的值. x,y 满足x(x-2)-y(y-6)=-10,求x,y的值 正数x,y满足x-y=2xy,求x-y/x+y的值. 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 如果X,Y为有理数,且X,Y满足条件/ X /=5,/ y /=2,/ x-y /=x-y ,求X+2Y的值. 如果x,y表示有理数,且x,y满足条件/x/=5,/y/=2,/x-y/=y-x,求x+2y的值.呜呜, 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 若x+y分之x-y=3,求式子x+y分之5(x-y)—2(x-y)分之x+y的值 若x-y分之x+y=3,求式子x+y分之5(x-y)—2（x-y）分之x+y的值 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 已知x+y=-5,x*x+y*y=19求xy和（x-y)*(x-y)的值 x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值 已知2/x+2/y=根号24,求 x/y(x-y) - y/x(x-y)的值