| 600 | ( | x | − | 40 | ) | = | 700 | ( | x | − | 88 | ) |
| 方程左边 = | 600 | x | − | 600 | × | 40 |
| = | 600 | x | − | 24000 |
| 600 | x | − | 24000 | = | 700 | ( | x | − | 88 | ) |
| 方程右边 = | 700 | x | − | 700 | × | 88 |
| = | 700 | x | − | 61600 |
| 600 | x | − | 24000 | = | 700 | x | − | 61600 |
| 600 | x | − | 700 | x | = | - | 61600 | + | 24000 |
| - | 100 | x | = | - | 61600 | + | 24000 |
| - | 100 | x | = | - | 37600 |
| 37600 | = | 100 | x |
| 100 | x | = | 37600 |
| x | = | 37600 | ÷ | 100 |
| = | 37600 | × | 1 100 |
| = | 376 | × | 1 |
| x | = | 376 |