| 3 | − | ( | 13 | + | 4 | ( | 6 | + | x | ) | ) | = | - | 2 | ( | - | x | − | 3 | ) |
| 方程左边 = | 3 | − | 13 | − | 4 | ( | 6 | + | x | ) |
| = | - | 10 | − | 4 | ( | 6 | + | x | ) |
| = | - | 10 | − | 4 | × | 6 | − | 4 | x |
| = | - | 10 | − | 24 | − | 4 | x |
| = | - | 34 | − | 4 | x |
| - | 34 | − | 4 | x | = | - | 2 | ( | - | x | − | 3 | ) |
| 方程右边 = | 2 | x | + | 2 | × | 3 |
| = | 2 | x | + | 6 |
| - | 34 | − | 4 | x | = | 2 | x | + | 6 |
| - | 4 | x | − | 2 | x | = | 6 | + | 34 |
| - | 6 | x | = | 6 | + | 34 |
| - | 6 | x | = | 40 |
| - | 40 | = | 6 | x |
| 6 | x | = | - | 40 |
| x | = | - | 40 | ÷ | 6 |
| = | - | 40 | × | 1 6 |
| = | - | 20 | × | 1 3 |
| x | = | - | 20 3 |
| x | = | - 6.666667 |