2x-y-z=3 4x+2y -z=15 4x+3y =18
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
解方程组x-4y+z=-3,2x+y-z=18,x-y-z=7.
已知x:y:z=2:3:4,且x+y+z=18,求x,y,z的值
{4x-9z=17 3x+y+15z=18 x+2y+3z=2
4X-9Z=17 3X+Y+15Z=18 X+2Y+3Z=2
{4x-9z=17{3x+y+15z=18{x+2y+3z=2
4x-5z=17 3x+y+15z=18 x+2y+3z=2
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
2x-y-z=3 4x+2y-z=15 4x+3y=18
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-
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