| - | 7 | ( | 3 | + | 5 | ( | 9 | + | 2 | x | ) | ) | − | 16 | = | - | 2 |
| 方程左边 = | - | 7 | × | 3 | − | 7 | × | 5 | ( | 9 | + | 2 | x | ) | − | 16 |
| = | - | 21 | − | 35 | ( | 9 | + | 2 | x | ) | − | 16 |
| = | - | 37 | − | 35 | ( | 9 | + | 2 | x | ) |
| = | - | 37 | − | 35 | × | 9 | − | 35 | × | 2 | x |
| = | - | 37 | − | 315 | − | 70 | x |
| = | - | 352 | − | 70 | x |
| - | 352 | − | 70 | x | = | - | 2 |
| - | 70 | x | = | - | 2 | + | 352 |
| - | 70 | x | = | 350 |
| - | 350 | = | 70 | x |
| 70 | x | = | - | 350 |
| x | = | - | 350 | ÷ | 70 |
| = | - | 350 | × | 1 70 |
| = | - | 5 | × | 1 |
| x | = | - | 5 |