| 126 | ( | 2 | ÷ | 9 | ) | − | ( | 2 | ÷ | 9 | ) | x | + | 7 | = | 1 | ÷ | 6 | × | x |
| 方程左边 = | 126 | × | 2 | ÷ | 9 | − | ( | 2 | ÷ | 9 | ) | x | + | 7 |
| = | 28 | − | ( | 2 | ÷ | 9 | ) | x | + | 7 |
| = | 35 | − | ( | 2 | ÷ | 9 | ) | x |
| = | 35 | − | 2 | ÷ | 9 | × | x |
| = | 35 | − | 2 9 | x |
| 35 | − | 2 9 | x | = | 1 | ÷ | 6 | × | x |
| 方程右边 = | 1 6 | x |
| 35 | − | 2 9 | x | = | 1 6 | x |
| - | 2 9 | x | − | 1 6 | x | = | - | 35 |
| - | 7 18 | x | = | - | 35 |
| 35 | = | 7 18 | x |
7 18 | x | = | 35 |
| x | = | 35 | ÷ | 7 18 |
| = | 35 | × | 18 7 |
| = | 5 | × | 18 |
| x | = | 90 |