若(z-3x)2+|y-2z|=0,则代数式x+2y+z等于___.
已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3
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x+2y-3z=0,2x+3y+5z=0,则x+y+zx-y+z= ___ .
若xyz不等于0,且|2x+3y-z|+(3x-y-z)^=0,则代数式z分之x+y=
若2x+5y+4z=0,3x+y-7z=0,则x+y-z的值等于( )
已知x=3y,z=7y(x≠0),求代数式2x+3y-z分之x+y+z的值
若(2x-3)2+(2x+y)2+|3z-y|=0,则x-y-z=___.
已知x=3y,z=7x(x不等于0),求代数式2x+3y-z分之x+y+z的值
若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
设xyz不 等于0,且2x-y+z=0,x+2y-5z=0,试求代数式(x-y)/(y+z) 的值
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3x+5y+6z=5,4x+2y+z=2,则x+y+z的值等于( )