设矩阵三阶A=（4 1 -2 ,2 2 1,3 1 -1）,B=（1 -3 ,2 2,3 -1）,求X使得AX=B

(A,B) =
4 1 -2 1 -3
2 2 1 2 2
3 1 -1 3 -1
r1-2r3,r2+r3
-2 -1 0 -5 -1
5 3 0 5 1
3 1 -1 3 -1
r2+3r1,r3+r1
-2 -1 0 -5 -1
-1 0 0 -10 -2
1 0 -1 -2 -2
r1-2r2,r3+r2
0 -1 0 15 3
-1 0 0 -10 -2
0 0 -1 -12 -4
ri*(-1),i=1,2,3; 交换行
1 0 0 10 2
0 1 0 -15 -3
0 0 1 12 4
X =
10 2
-15 -3
12 4