| ( | 6 | − | x | ) | ( | 6 | − | x | ) | + | ( | 2 | x | ) | ( | 2 | x | ) | = | 6 |
| 方程左边 = | 6 | ( | 6 | − | x | ) | − | x | ( | 6 | − | x | ) | + | ( | 2 | x | ) | ( | 2 | x | ) |
| = | 6 | × | 6 | − | 6 | x | − | x | ( | 6 | − | x | ) | + | ( | 2 | x | ) | ( | 2 | x | ) |
| = | 36 | − | 6 | x | − | x | ( | 6 | − | x | ) | + | ( | 2 | x | ) | ( | 2 | x | ) |
| = | 36 | − | 6 | x | − | x | × | 6 | + | x | x | + | ( | 2 | x | ) | ( | 2 | x | ) |
| = | 36 | − | 12 | x | + | x | x | + | ( | 2 | x | ) | ( | 2 | x | ) |
| = | 36 | − | 12 | x | + | x | x | + | 2 | x | ( | 2 | x | ) |
| = | 36 | − | 12 | x | + | x | x | + | 2 | x | × | 2 | x |
| = | 36 | − | 12 | x | + | x | x | + | 4 | x | x |
| 36 | − | 12 | x | + | x | x | + | 4 | x | x | = | 6 |