x-3y-2z=27 2x+3y+z=-5 3x+3y-z=4
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
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
求解三元一次方程组:{x+y/2=y+z/3=z+x/4 x+y+z=27
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
已知x:y:z=3:4:5,3x+2y-4z=18.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.
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
2x+5y+4z=0,3x+y-7z=0,则x+y-z=?
解方程组:x+y+z=4,x+y+2z=5,3x+y-z=6