| 2 | x | − | ( | x | + | 10 | ) | = | 5 | x | + | 2 | ( | x | + | 1 | ) |
| 方程左边 = | 2 | x | − | x | − | 10 |
| = | 1 | x | − | 10 |
| 1 | x | − | 10 | = | 5 | x | + | 2 | ( | x | + | 1 | ) |
| 方程右边 = | 5 | x | + | 2 | x | + | 2 | × | 1 |
| = | 5 | x | + | 2 | x | + | 2 |
| = | 7 | x | + | 2 |
| 1 | x | − | 10 | = | 7 | x | + | 2 |
| 1 | x | − | 7 | x | = | 2 | + | 10 |
| - | 6 | x | = | 2 | + | 10 |
| - | 6 | x | = | 12 |
| - | 12 | = | 6 | x |
| 6 | x | = | - | 12 |
| x | = | - | 12 | ÷ | 6 |
| = | - | 12 | × | 1 6 |
| = | - | 2 | × | 1 |
| x | = | - | 2 |