4x+2y-z=2 (1)
3x-y+2z=10 (2)
11x+3y=8 (3)
(1)*2 8x+4y-2z=4 (4)
(2)+(4) 12x+6y=6 (5)
(3)*2 22x+6y=16 (6)
(6)-(5) 10x=10
x=1
带入(5)y=-1
带入(1)z=-2
4x+2y-z=2 (1)
3x-y+2z=10 (2)
11x+3y=8 (3)
(1)*2 8x+4y-2z=4 (4)
(2)+(4) 12x+6y=6 (5)
(3)*2 22x+6y=16 (6)
(6)-(5) 10x=10
x=1
带入(5)y=-1
带入(1)z=-2