| ( | 3 | x | + | 1 | ) | ÷ | 2 | = | ( | 2 | x | − | 1 | ) |
| 方程左边 = | 3 | x | × | 1 2 | + | 1 | × | 1 2 |
| = | 3 2 | x | + | 1 2 |
3 2 | x | + | 1 2 | = | ( | 2 | x | − | 1 | ) |
| 方程右边 = | 2 | x | − | 1 |
3 2 | x | + | 1 2 | = | 2 | x | − | 1 |
3 2 | x | − | 2 | x | = | - | 1 | − | 1 2 |
| - | 1 2 | x | = | - | 1 | − | 1 2 |
| - | 1 2 | x | = | - | 3 2 |
3 2 | = | 1 2 | x |
1 2 | x | = | 3 2 |
| x | = | 3 2 | ÷ | 1 2 |
| = | 3 2 | × | 2 |
| = | 3 | × | 1 |
| x | = | 3 |