已知x=y+3,求代数式3(x-y)²-½(x-y)+¾(x-y)-2(x-y)²
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
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,求代数式3(x-y)²-½(x-y)+¾(x-y)-2(x-y)²
已知x+3y=2,求代数式(x²-y²/x+y)-【2(x+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=3,求代数式3(x+y)
已知x/y=3/2求代数式4x-9y/2x+3y
已知x-y=3,求代数式7-x+y-(y-x)^2的值.
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值
已知x-y除以x+y=3,求代数式x+y分之2(x-y)-3(x-y)分之x+y的值.
已知x-y/x+y=2,求代数式2(x-y)/x+y + x+y/3(x-y)的值 快啊.