解方程组：I.x+2y-z=6 2x+y+z=9 3x+4y+z=18 II.x-y=3 x²-y²

解方程组：I.x+2y-z=6 2x+y+z=9 3x+4y+z=18 II.x-y=3 x²-y² 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 解方程组2x+y-3z=1,x-2y+z=6,3x-y+2z=9求x,y,z的值 x+y/2=z+x/3+y=z/4,...x+y+z=27.解方程组. 解三元一次方程组：x+y+z=6,y-z=4,x-y-2z=3, 解方程组{x(x+y+z)=6,y(x+y+z)=12,z(x+y+z)=18 x/2=y/3=z/4 x+y+z=18 求方程组解 解方程组{6x=4y=3z,2x+y+z=22 解方程组1、4x+9y=12,3y-2z=1,2x+6z=32、3x-y+2z=3,2x+y-3z=11,x+y+z=1 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