如果x+2y-z=1.2x+y-2z=2则x+y-z=?

如果x+2y-z=1.2x+y-2z=2则x+y-z=? 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, 如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少 如果x+y=2z,且x≠y,那么x/(x-z)+y/(y-z)等于( )急 如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少 如果,根号x-3+| y-2 |+z^2=2z-1 求 （x+z)^y 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? (x-2y+z)(x+y-2z)分之（y-x)(z-x) + (x+y-2z)(y+z-2x)分之(z-y)(x-y) + (y+z-2z)(x-2y+z)分之（x-z)(y-z)=?第三部分那个是 （y+z-2x)(x-2y+z)分之（x-z)(y-z) 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 已知：x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值. x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 如果x=3y,z=x/2,那么(x-y+z)/(x+y+z)=多少? 如果x/2=y/3=z/4,且x+y+z=18,那么x+y-z=? 如果x/2=y/3=z/4,求(2x-y+3z)/(x+y-z)的值 如果2x-3y=z x+3y-14z=0 求x:y:z 快, 如果x:y=3:2,y:Z=4：2,那么x：y：Z= 如果x:y=2:3,y:z=4:3,则x:y:z=