| 4700 | x | + | 7900 | ( | 6 | − | x | ) | = | 40000 |
| 方程左边 = | 4700 | x | + | 7900 | × | 6 | − | 7900 | x |
| = | 4700 | x | + | 47400 | − | 7900 | x |
| = | - | 3200 | x | + | 47400 |
| - | 3200 | x | + | 47400 | = | 40000 |
| - | 3200 | x | = | 40000 | − | 47400 |
| - | 3200 | x | = | - | 7400 |
| 7400 | = | 3200 | x |
| 3200 | x | = | 7400 |
| x | = | 7400 | ÷ | 3200 |
| = | 7400 | × | 1 3200 |
| = | 37 | × | 1 16 |
| x | = | 37 16 |
| x | = | 2.3125 |