| 1 | − | ( | x | − | 13 | ) | ÷ | 3 | = | ( | 9 | − | 3 | x | ) | + | x |
| 方程左边 = | 1 | − | x | × | 1 3 | + | 13 | × | 1 3 |
| = | 1 | − | x | × | 1 3 | + | 13 3 |
| = | 16 3 | − | 1 3 | x |
16 3 | − | 1 3 | x | = | ( | 9 | − | 3 | x | ) | + | x |
| 方程右边 = | 9 | − | 3 | x | + | x |
| = | 9 | − | 2 | x |
16 3 | − | 1 3 | x | = | 9 | − | 2 | x |
| - | 1 3 | x | + | 2 | x | = | 9 | − | 16 3 |
5 3 | x | = | 9 | − | 16 3 |
5 3 | x | = | 11 3 |
| x | = | 11 3 | ÷ | 5 3 |
| = | 11 3 | × | 3 5 |
| = | 11 | × | 1 5 |
| x | = | 11 5 |
| x | = | 2.2 |