已知x²+y²=2x+8y-17
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x²+y²-2x+8y+17=0,求2x²-3y的值,
已知x²+y²-2x+8y+17=0,求2x²+3y的值
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知x²+y²=2x+8y-17
已知P=x²/x-y-y²/x-y,Q=(x+y)²-2y(x+y),小红、小华两人在x=
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
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+
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
已知:x²y²-2x+6y+10=0则x+y=
已知x²+4x+y²-2y+5=0,则x+y=
已知x²+y²-2x+4y+5=0,求x+y