2y+z=3y ① ,x+3y-z=8,② x+y+2z=13③ 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) 已知x/2=y/4=z/7,求①x：y：z.②若2x+y+3z=58,分别求x,y,z的值.③求x+y/x+z的值. x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, ①x+y+z=6 3x-y+2z=12 x-y-3z=-4 ②x+y-z=2 4x-2y+3y+8=0 x+3y-2z- x/2=y/3=z/5 x+3y-z/x-3y+z 如果,根号x-3+| y-2 |+z^2=2z-1 求 （x+z)^y {3x+2y+z=13 x+y+2z=7 2x+3y-z=12,求x,y,z 已知4x-3y+z=0,x+2y-8z=0,xyz不等于0,求x+y-z/x-y+2z的值 {x+y+z=1;x+3y+7z=-1;z+5y+8z=-2 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 (x+y-z)(x-y+z)=