| 3 | ( | ( | 2 | ( | x | − | 19 | ) | + | 5 | ) | + | 9 | ) | − | 7 | = | - | x | + | 26 |
| 方程左边 = | 3 | ( | 2 | ( | x | − | 19 | ) | + | 5 | ) | + | 3 | × | 9 | − | 7 |
| = | 3 | ( | 2 | ( | x | − | 19 | ) | + | 5 | ) | + | 27 | − | 7 |
| = | 3 | ( | 2 | ( | x | − | 19 | ) | + | 5 | ) | + | 20 |
| = | 3 | × | 2 | ( | x | − | 19 | ) | + | 3 | × | 5 | + | 20 |
| = | 6 | ( | x | − | 19 | ) | + | 15 | + | 20 |
| = | 6 | ( | x | − | 19 | ) | + | 35 |
| = | 6 | x | − | 6 | × | 19 | + | 35 |
| = | 6 | x | − | 114 | + | 35 |
| = | 6 | x | − | 79 |
| 6 | x | − | 79 | = | - | x | + | 26 |
| 6 | x | + | x | = | 26 | + | 79 |
| 7 | x | = | 26 | + | 79 |
| 7 | x | = | 105 |
| x | = | 105 | ÷ | 7 |
| = | 105 | × | 1 7 |
| = | 15 | × | 1 |
| x | = | 15 |