| ( | x | − | 3 | ) | ( | x | + | 3 | ) | ( | x | − | 6 | ) | = | 5 |
| 方程左边 = | x | ( | x | + | 3 | ) | ( | x | − | 6 | ) | − | 3 | ( | x | + | 3 | ) | ( | x | − | 6 | ) |
| = | x | x | ( | x | − | 6 | ) | + | x | × | 3 | ( | x | − | 6 | ) | − | 3 | ( | x | + | 3 | ) | ( | x | − | 6 | ) |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | ( | x | − | 6 | ) | − | 3 | ( | x | + | 3 | ) | ( | x | − | 6 | ) |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | x | × | 3 | × | 6 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | x | × | 18 | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 18 | x | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 18 | x | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 18 | x | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 18 | x | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 0 | x | − | 3 |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 3 | x | x |
| = | x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 3 | x | x |
| x | x | x | − | x | x | × | 6 | + | x | × | 3 | x | − | 3 | x | x | = | 5 |