若y=3x,z=2y,则x=y=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{x+3y+10z=0 则 (x+y-z)/(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)
(x+y-z)(x-y+z)=
y=-2X,Z=3y,那么X-Y+(-Z)等于
已知x+y=3,y+z=4,x+z=5,则x+y+z等于( )
若x/3=y/2=z/5,则2x-3y-z/x-y+z=
x/2=y/3=z/5 x+3y-z/x-3y+z
如果x/2=y/7=z/5,x,y,z都不等于0,则(x+y+z)/(3x-y)等于多少?
若3x+5y+6z=5,4x+2y+z=2,则x+y+z的值等于【】
若3x+5y+6z=5,4x+2y+z=2,则x+y+z的值等于( )
若2x+5y+4z=0,3x+y-7z=0,则x+y-z的值等于( )