如果2x-3y=z x+3y-14z=0 求x:y:z 快,

如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, 如果,根号x-3+| y-2 |+z^2=2z-1 求 （x+z)^y 快已知方程组；x+y-7z=0 3x-2y-z=0,且z≠0,求x：y：z加减消元法 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3 已知 3x-y+2z=0 2x+y-3z=0,求x :y :z. 设X+Y+Z=0求X^3+X^2Z-XYZ+Y^2Z+Y^3的值 若x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值 已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y- x+2y+3z=14 2x+y+z=7 3x+y+2z=11 求x y z x+y-z=6 x-3y+2z=0 3x+2y-z=0 求x、y、z 要过程