| 56143 | − | 3000 | = | X | + | 687 10000 | X | + | ( | 56143 | − | X | ) | × | 687 10000 |
| 方程左边 = | 53143 |
| 53143 | = | X | + | 687 10000 | X | + | ( | 56143 | − | X | ) | × | 687 10000 |
| 方程右边 = | 10687 10000 | X | + | ( | 56143 | − | X | ) | × | 687 10000 |
| 53143 | = | 10687 10000 | X | + | ( | 56143 | − | X | ) | × | 687 10000 |
| 方程右边 = | 10687 10000 | X | + | 56143 | × | 687 10000 | − | X | × | 687 10000 |
| = | 10687 10000 | X | + | 38570241 10000 | − | X | × | 687 10000 |
| = | 1 | X | + | 38570241 10000 |
| 53143 | = | 1 | X | + | 38570241 10000 |
| - | 1 | X | = | 38570241 10000 | − | 53143 |
| - | X | = | 38570241 10000 | − | 53143 |
| - | X | = | - | 492859759 10000 |
492859759 10000 | = | X |
| X | = | 492859759 10000 |