已知2x-2y-5=1,求[2(x-y)^2-3(x-y)]÷(y-x)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-2y=2012,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷8x的值
已知x-2y=2011,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷4x的值.
已知3x-4y/2x+y=1/2 求x/y的值
已知3x-2y/x+y=5/3求x;y的值
已知|2x-3y|+|3x-y-1|=0,求x,y的值.
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知1/x+1/y=5,求(2x-3y+2y)/(x+2xy+y)的值
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x+y=-1,xy=-2,求代数式-5(x+y)+(x-y)+x(xy+y)的值
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
已知2/x+2/y=根号24,求 x/y(x-y) - y/x(x-y)的值