x+y=9 x-y=3则2x²-2y²=
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
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=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x,y的值满足方程组x+2y=3,x-y=-2,求x/(x-y)²+x²-y²/(x+
化简后求值 [(x-2y)²+(x-2y)(x-2y)-2x(2x-y)]÷2x 其中x=2 y=3
若【2x²-3y²-10y+5】²+根号x-2y,则x= y=
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知y-2x=0,求3x²-2y²/(x+y)(x-y)的值