题目应是x+y-z=6(1)
x+3y+2z=1(2)
3x+2y-z=4(3)
(1)-(2)
x+y-z-x-3y-2z=6-1
-2y-3z=5 (4)
(1)*3-(3)
3x+3y-3z-3x-2y+z=18-4
y-2z=14 (5)
(5)*2+(4)
2y-4z-2y-3z=28+5
-7z=33
z=-33/7
y=32/7
x=-23/7