{2x+y+3z=13,4x+2y+z=11,6x+y+4z=20}
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
1.x+y=16,y+z=12,z+x=102.3x-y+z=4,2x+3y-z=12,x+y+z=63.x+y+z=6
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
{2x+y+3z=13,4x+2y+z=11,6x+y+4z=20}
x+2y+4z=17 2x+y+z=7 3x+y+2z=11
x+y+z=4 2x+3y-z=6 3x+2y+2z=10
2x-y+2z=-17 3x+y-3z=-4 x+y+z=6
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6}
解方程{3x -y+z=4 2x+3y-z=12 x+y+z=6
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z