| ( | x | x | + | 25 | ) | ( | x | x | + | 25 | ) | ( | x | x | + | 100 | ) | = | 62500 |
| 方程左边 = | x | x | ( | x | x | + | 25 | ) | ( | x | x | + | 100 | ) | + | 25 | ( | x | x | + | 25 | ) | ( | x | x | + | 100 | ) |
| = | x | x | x | x | ( | x | x | + | 100 | ) | + | x | x | × | 25 | ( | x | x | + | 100 | ) | + | 25 | ( | x | x | + | 25 | ) | ( | x | x | + | 100 | ) |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| = | x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x |
| x | x | x | x | x | x | + | x | x | x | x | × | 100 | + | x | = | 62500 |