3x+4y+z=14 x+5y+2z=17 2x+2y-z=3
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
已知2x+5y+4z=15.7x+y+3z=14 则x+y+z=?
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
(1)3x+4z=7;2x+3y+z=9;5x-9y+7z=8 (2)3x+4y+z=14;x+5y+2z=17;2x+
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
4x-5z=17 3x+y+15z=18 x+2y+3z=2
x+2y+4z=17 2x+y+z=7 3x+y+2z=11
2x-y+2z=-17 3x+y-3z=-4 x+y+z=6
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?