5x+2y=x+3z ; 3x+3y=2y+2z ; x+2y+z=nx; 求n
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
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
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-
已知3x=4y,2y=5z,试求x:y:z
3x=4y 2y=5z 试求x:y:z
x/3=y/4=z/5,求x+y+z/3x-2y+z的值,
若x/3=y/4=z/5,求x+y+z/3x-2y+z的值.
x+2y+3z=20,x+3y+5z=31,求x+y+z的值
已知x:y:z=3:4:5,3x+2y-4z=18.求:x+y+z.
2分之x=3分之y=5分之z x+y+z=20 求x,y,z