3x-y=-7,y+2z=2,2x-2z=-5 求x,y,z
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
x/2=y/3=z/5 x+3y-z/x-3y+z
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
已知x:y:z=4:5:7,求:(1)2x+3y+z/5z; (2)x+y/y+z.
1.已知x:y:z=4:5:7,求:(一)2x+3y+z/5z; (二)x+y/y+z 非常急,
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10
已知2x+5y+4z=6.3x+y-7z=-4 求 x+2y+z