| 8000 | ÷ | x | = | 13000 | ÷ | ( | x | + | 5 | ) |
| 方程两边同时乘以: | x | , | ( | x | + | 5 | ) |
| 8000 | ( | x | + | 5 | ) | = | 13000 | x |
| 8000 | x | + | 8000 | × | 5 | = | 13000 | x |
| 8000 | x | + | 40000 | = | 13000 | x |
| 8000 | x | − | 13000 | x | = | - | 40000 |
| - | 5000 | x | = | - | 40000 |
| 40000 | = | 5000 | x |
| 5000 | x | = | 40000 |
| x | = | 40000 | ÷ | 5000 |
| = | 40000 | × | 1 5000 |
| = | 8 | × | 1 |
| x | = | 8 |