若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z)
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
4x-3y-6z=0,x+2y-7z=0是一个方程组,那么x-y+z/x+y+z的值等于
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
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
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+y+z=1;x+3y+7z=-1;z+5y+8z=-2
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
若2x+5y+4z=6,3x+y-7z=-4,那么x+y-z的值是多少?
1.(x+y-z)+(x-y+z)-(x-y-z) 2.2x-(3x-2y+3)-(5y-2)
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,