| 4 | ( | 2 | x | − | 1 | ) | − | 3 | ( | 5 | x | + | 1 | ) | = | 24 |
| 方程左边 = | 4 | × | 2 | x | − | 4 | × | 1 | − | 3 | ( | 5 | x | + | 1 | ) |
| = | 8 | x | − | 4 | − | 3 | ( | 5 | x | + | 1 | ) |
| = | 8 | x | − | 4 | − | 3 | × | 5 | x | − | 3 | × | 1 |
| = | 8 | x | − | 4 | − | 15 | x | − | 3 |
| = | - | 7 | x | − | 7 |
| - | 7 | x | − | 7 | = | 24 |
| - | 7 | x | = | 24 | + | 7 |
| - | 7 | x | = | 31 |
| - | 31 | = | 7 | x |
| 7 | x | = | - | 31 |
| x | = | - | 31 | ÷ | 7 |
| = | - | 31 | × | 1 7 |
| x | = | - | 31 7 |
| x | = | - 4.428571 |