1   -2    0    0   3
2   -5   -3   -2   6
0    5   15   10   0
2    6   18    8   6

((row 2) - ((row 1) *2))*-1
1   -2    0    0   3
0    1    3    2   0
0    5   15   10   0
2    6   18    8   6

(row 3) - ((row 2)*5)
1   -2    0    0   3
0    1    3    2   0
0    0    0    0   0
2    6   18    8   6

Switch row 3 and 4
1   -2    0    0   3
0    1    3    2   0
2    6   18    8   6
0    0    0    0   0

((row 3) - (row 1)*2)
1   -2    0    0   3
0    1    3    2   0
0   10   18    8   0
0    0    0    0   0

((row 3) - (row 2)*10)
1   -2    0    0   3
0    1    3    2   0
0    0  -12  -12   0
0    0    0    0   0

(row 3) /-12
1   -2    0    0   3
0    1    3    2   0
0    0    1    1   0
0    0    0    0   0