| ( | 6600 | − | X | ) | ( | 1 | − | X | ) | ( | 1 | − | X | ) | = | 4100 |
| 方程左边 = | 6600 | ( | 1 | − | X | ) | ( | 1 | − | X | ) | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | × | 1 | ( | 1 | − | X | ) | − | 6600 | X | ( | 1 | − | X | ) | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | ( | 1 | − | X | ) | − | 6600 | X | ( | 1 | − | X | ) | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | × | 1 | − | 6600 | X | − | 6600 | X | ( | 1 | − | X | ) | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | − | 6600 | X | − | 6600 | X | ( | 1 | − | X | ) | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | − | 6600 | X | − | 6600 | X | × | 1 | + | 6600 | X | X | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | − | 6600 | X | − | 6600 | X | + | 6600 | X | X | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | − | 13200 | X | + | 6600 | X | X | − | X | ( | 1 | − | X | ) | ( | 1 | − | X | ) |
| = | 6600 | − | 13200 | X | + | 6600 | X | X | − | X | × | 1 | ( | 1 | − | X | ) | + | X | X | ( | 1 | − | X | ) |
| = | 6600 | − | 13200 | X | + | 6600 | X | X | − | X | × | 1 | × | 1 | + | X | × | 1 | X |
| = | 6600 | − | 13200 | X | + | 6600 | X | X | − | X | × | 1 | + | X | × | 1 | X | + | X |
| = | 6600 | − | 13201 | X | + | 6600 | X | X | + | X | × | 1 | X | + | X | X | ( | 1 | − | X | ) |
| = | 6600 | − | 13201 | X | + | 6600 | X | X | + | X | × | 1 | X | + | X | X | × | 1 |
| 6600 | − | 13201 | X | + | 6600 | X | X | + | X | × | 1 | X | + | X | X | × | 1 | = | 4100 |