x²-y²=24,x+y=6,求x+2y的值
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
已知2/x+2/y=根号24,求 x/y(x-y) - y/x(x-y)的值
已知2/x 2/y=根号24,求 x/y(x-y) - y/x(x-y)的值
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+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+
若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
已知x²-y²=12,x+y=6,求x,y的值
已知x²+4y²-6x+8y+13=0,求x-y/x+y的值.
已知x² +y²+5/4=2x+y,求y-x的值
已知y-2x=0,求3x²-2y²/(x+y)(x-y)的值
已知x+3y=2,求代数式(x²-y²/x+y)-【2(x+y)】的值