x-2y+3z=0,3x+2y+5z=12,2x-4y-z=-7.解方程组

解方程组x-4y+z=-3,2x+y-z=18,x-y-z=7. 解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6} 解方程组：x+y+z=4,x+y+2z=5,3x+y-z=6 已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z x-2y+3z=0,3x+2y+5z=12,2x-4y-z=-7.解方程组 解方程组{z=x+y 3x-2y-2z=-5 2x+y-z=3 解方程组 z=x+y 2x-3y+2z=5 x+2y-z=3 解方程组{2x+3y+z=11,x+y+z=0,3x-y+z=-2. x+y/2=z+x/3+y=z/4,...x+y+z=27.解方程组. 已知x,y,z满足方程组：4x-5y+2z=o;x+4y-3x=0,求x:y:z的值 方程组:x-2y+4z=0,2x+3y-3z=0...xyz不等于0,求(2x+y-z)\(2x-y+z) 已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少