增广矩阵 =
2 7 3 1 6
3 5 2 2 4
9 4 1 7 2
r3-3r2,r2-r1
2 7 3 1 6
1 -2 -1 1 -2
0 -11 -5 1 -10
r1-2r2
0 11 5 -1 10
1 -2 -1 1 -2
0 -11 -5 1 -10
r3+r1,r1*(1/11),r2+2r1
0 1 5/11 -1/11 10/11
1 0 -1/11 9/11 -2/11
0 0 0 0 0
交换行
1 0 -1/11 9/11 -2/11
0 1 5/11 -1/11 10/11
0 0 0 0 0
方程组的通解为:(-2/11,10/11,0,0)'+c1(1,-5,11,0)'+c2(9,-1,0,11)'.