| ( | 4 | − | x | ) | ( | x | − | 4 | ) | = | 4 | ( | 3 | − | x | ) | ( | x | − | 2 | ) |
| 方程左边 = | 4 | ( | x | − | 4 | ) | − | x | ( | x | − | 4 | ) |
| = | 4 | x | − | 4 | × | 4 | − | x | ( | x | − | 4 | ) |
| = | 4 | x | − | 16 | − | x | ( | x | − | 4 | ) |
| = | 4 | x | − | 16 | − | x | x | + | x | × | 4 |
| = | 8 | x | − | 16 | − | x | x |
| 8 | x | − | 16 | − | x | x | = | 4 | ( | 3 | − | x | ) | ( | x | − | 2 | ) |
| 方程右边 = | 4 | × | 3 | ( | x | − | 2 | ) | − | 4 | x | ( | x | − | 2 | ) |
| = | 12 | ( | x | − | 2 | ) | − | 4 | x | ( | x | − | 2 | ) |
| = | 12 | x | − | 12 | × | 2 | − | 4 | x | ( | x | − | 2 | ) |
| = | 12 | x | − | 24 | − | 4 | x | ( | x | − | 2 | ) |
| = | 12 | x | − | 24 | − | 4 | x | x | + | 4 | x | × | 2 |
| = | 12 | x | − | 24 | − | 4 | x | x | + | 8 | x |
| = | 20 | x | − | 24 | − | 4 | x | x |
| 8 | x | − | 16 | − | x | x | = | 20 | x | − | 24 | − | 4 | x | x |