已知y-2x=10,求[2y(x-y)-(x-y)²+(x+y)²-2xy]÷4y的值

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y 已知x≠y,x^2-x=y^2-y,求x+y的值. 已知x^2+2x+y^2-6y+10=0 求（x+y)^2 已知x+y=4,x^2+y^2=10,求(x-y)^2 已知x+y=10,x^3+y^3=400,求x^2+y^2 已知x^2+6x+y^2+10y=-34 求x.y 已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y 就是已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y /4y就是除以4y 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 已知2x-y=10,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y (4xy-2y²)/4y是怎么变成=2y(2x-y)÷4y 已知x^2+y^2--6x--2y+10=0,求x+y/x--y 已知x^2+y^2+6x-2y+10=0,求x+y/x-y的值谢谢 已知x^2-2x+y^2+6y+10=0,求分式x-y/x+y的值 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知x^2+y^2-10x-12y+61=0,求x/y-y/x的值 已知：4x^2+y^2-4x-6y+10=0,求y/x-x/y的值