| ( | 55 | − | x | ) | ( | 5 | − | x | ) | ( | 5 | − | x | ) | = | 1 |
| 方程左边 = | 55 | ( | 5 | − | x | ) | ( | 5 | − | x | ) | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 55 | × | 5 | ( | 5 | − | x | ) | − | 55 | x | ( | 5 | − | x | ) | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 275 | ( | 5 | − | x | ) | − | 55 | x | ( | 5 | − | x | ) | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 275 | × | 5 | − | 275 | x | − | 55 | x | ( | 5 | − | x | ) | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 1375 | − | 275 | x | − | 55 | x | ( | 5 | − | x | ) | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 1375 | − | 275 | x | − | 55 | x | × | 5 | + | 55 | x | x | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 1375 | − | 275 | x | − | 275 | x | + | 55 | x | x | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 1375 | − | 550 | x | + | 55 | x | x | − | x | ( | 5 | − | x | ) | ( | 5 | − | x | ) |
| = | 1375 | − | 550 | x | + | 55 | x | x | − | x | × | 5 | ( | 5 | − | x | ) | + | x | x | ( | 5 | − | x | ) |
| = | 1375 | − | 550 | x | + | 55 | x | x | − | x | × | 5 | × | 5 | + | x | × | 5 | x |
| = | 1375 | − | 550 | x | + | 55 | x | x | − | x | × | 25 | + | x | × | 5 | x | + | x |
| = | 1375 | − | 575 | x | + | 55 | x | x | + | x | × | 5 | x | + | x | x | ( | 5 | − | x | ) |
| = | 1375 | − | 575 | x | + | 55 | x | x | + | x | × | 5 | x | + | x | x | × | 5 |
| 1375 | − | 575 | x | + | 55 | x | x | + | x | × | 5 | x | + | x | x | × | 5 | = | 1 |