2x-3y+4z=-4;3x=y-2z;5x+2y+3z=2
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
已知x:y:z=3:4:5,3x+2y-4z=18.求:x+y+z.
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
已知方程组4x-5y+2z=0 x+2y=3z 则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.
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
2x+5y+4z=0,3x+y-7z=0,则x+y-z=?