x+y=7,x·y=3,求x²+y²
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
若x+7y=y-3x,求x
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x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
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)
y²+3x=7,y³+x=3,求y等于几.
已知x²-x=7,y²-y=7,若x≠y,求x+y的值
x/y=3,求x²+y²-xy/x²-y²的值.
已知x²+y²=25,x+y=7,且x>y,求x-y的值
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知x²+y²=25,x+y=7,求x-y的值.