| 16000 | = | 15 | X | − | 7 | ( | X | − | 168000 | ) |
| 方程右边 = | 15 | X | − | 7 | X | + | 7 | × | 168000 |
| = | 15 | X | − | 7 | X | + | 1176000 |
| = | 8 | X | + | 1176000 |
| 16000 | = | 8 | X | + | 1176000 |
| - | 8 | X | = | 1176000 | − | 16000 |
| - | 8 | X | = | 1160000 |
| - | 1160000 | = | 8 | X |
| 8 | X | = | - | 1160000 |
| X | = | - | 1160000 | ÷ | 8 |
| = | - | 1160000 | × | 1 8 |
| = | - | 145000 | × | 1 |
| X | = | - | 145000 |