z=3x+4y,(2
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)
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
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
x+y+z=2 4x+2y+z=4 2x+3y+z=1
x-y+4z=10,x+3y+2z=2,x+2y+3z=11.
x+2y+3z=10,x-y+4z=10,x+3y+2z=2
x+y+z=4 2x+3y-z=6 3x+2y+2z=10
已知,x/2=y/3=z/4,则(2x+y-z)/(3x-2y+z)=?
解方程:{2x+3y+z=7,x+y+z=4,3x+y-z=-4
2x-y+2z=-17 3x+y-3z=-4 x+y+z=6
x+2y+4z=17 2x+y+z=7 3x+y+2z=11