| p | × | 2 | ( | p | + | 3 | ) | × | 2 | = | 4 | ( | 1 | − | p | ) | × | 3 |
| 方程左边 = | p | × | 4 | ( | p | + | 3 | ) |
| p | × | 4 | ( | p | + | 3 | ) | = | 4 | ( | 1 | − | p | ) | × | 3 |
| 方程左边 = | p | × | 4 | p | + | p | × | 4 | × | 3 |
| = | p | × | 4 | p | + | p | × | 12 |
| p | × | 4 | p | + | 12 | p | = | 4 | ( | 1 | − | p | ) | × | 3 |
| 方程右边 = | 12 | ( | 1 | − | p | ) |
| p | × | 4 | p | + | 12 | p | = | 12 | ( | 1 | − | p | ) |
| 方程右边 = | 12 | × | 1 | − | 12 | p |
| = | 12 | − | 12 | p |
| p | × | 4 | p | + | 12 | p | = | 12 | − | 12 | p |