| 4 | = | ( | - | 3 | ÷ | 2 | ) | ( | 5 | ÷ | 2 | ) | + | x | ÷ | 2 |
| 方程右边 = | - | 3 | ÷ | 2 | × | ( | 5 | ÷ | 2 | ) | + | 1 2 | x |
| = | - | 3 2 | ( | 5 | ÷ | 2 | ) | + | 1 2 | x |
| = | - | 3 2 | × | 5 | ÷ | 2 | + | 1 2 | x |
| = | - | 15 4 | + | 1 2 | x |
| 4 | = | - | 15 4 | + | 1 2 | x |
| - | 1 2 | x | = | - | 15 4 | − | 4 |
| - | 1 2 | x | = | - | 31 4 |
31 4 | = | 1 2 | x |
1 2 | x | = | 31 4 |
| x | = | 31 4 | ÷ | 1 2 |
| = | 31 4 | × | 2 |
| = | 31 2 | × | 1 |
| x | = | 31 2 |
| x | = | 15.5 |