全部加到第一行,提出一个10,然后化简|1 1 1 1 |10 |0 1 2 -1 |=|0 1 -2 -1 ||0 -3 -2 -1 | |1 1 1 1 |10 |0 1 2 -1 |=|0 0 -4 0 ||0 0 4 -4 | |1 1 1 1 |10 |0 1 2 -1 |=|0 0 -4 0 ||0 0 0 -4 | 10*-4*-4=160...