11x-3y+6z=1(1)
{2x+4y=7z(2)
{9y-3z=0(3)
由(3)
9y=3z
z=3y
代入(2)
2x+4y=21y
2x=17y
x=17y/2
代入(1)
187y/2-3y+18y=1
187y+30y=2
217y=2
y=2/217
z=6/217
x=17/217
x=5(1)
x+5y-2z=-4(2)
4x-3y+2z=1(3)
(1)代入(2),(3)
5y-2z=-9
-3y+2z=-19
2y=-28
y=-14
z=61/2
x=5
x+y=22(1)
x+z=-27(2)
y+z=13(3)
(1)-(2)
y-z=49
y+z=13
2y=62
y=31
z=31-49=-18
x=22-31=-9