解: 系数矩阵 =
11 -1 -1
2 -532
7 -731
r2-2r1, r3-7r1
11 -1 -1
0 -754
0 -14108
r3-2r2
11 -1 -1
0 -754
0000
r2*(-1/7)
11-1 -1
01 -5/7 -4/7
00 00
r1-r2
10 -2/7 -3/7
01 -5/7 -4/7
00 00
方程组的全部解为: c1(2,5,7,0)' + c2(3,4,0,7)'