[(x-y)²+(x+y)(x-y)]除以2x
【(x-y)^2+(x+y)(x-y)】除以 2x
2x-y=2,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
(x+y)²-2(x²-y²)+(y-x)²
x²-4y² x+2y
|x+2y+3|+(2x+y)²=0求x²-xy+y²
[(x+2y)²-(x+y)(3x-y)-5y²]÷(2x),其中x,y满足x²+4x+y
x²-4y²/x²+2xy+y²÷x+2y/2x²+2xy
已知非零实数x,y满足x²-4xy+4y²=0,求分式2x-y除以2x+y的值
已知x²+y²-4x-2y+5=0,则根号x+y除以根号x-y的值是多少?
化简:1.2x²-y²+(2y²-3x²)-(2y²+x²)
{(z+y)(x-y)-(x-y)的2次方+2y(x-y)}除以4y