{x+2y+3z=11,x-y+7z=10,x+3y+2z=2
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
x/2=y/3=z/5 x+3y-z/x-3y+z
x+2y+3z=14 2x+y+z=7 3x+y+2z=11
x+2y+4z=17 2x+y+z=7 3x+y+2z=11
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
x+2y+3z=14 2x+y+z=7 3x+y+2z=11 求x y z
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=——
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
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
2x+3y-z=11 2x+y-5z=8 -2+7y+z=19
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10