1 2 | ( | 8 | − | t | ) | ( | 12 | − | 2 | t | ) | = | 24 |
| 方程左边 = | 1 2 | × | 8 | ( | 12 | − | 2 | t | ) | − | 1 2 | t | ( | 12 | − | 2 | t | ) |
| = | 4 | ( | 12 | − | 2 | t | ) | − | 1 2 | t | ( | 12 | − | 2 | t | ) |
| = | 4 | × | 12 | − | 4 | × | 2 | t | − | 1 2 | t | ( | 12 | − | 2 | t | ) |
| = | 48 | − | 8 | t | − | 1 2 | t | ( | 12 | − | 2 | t | ) |
| = | 48 | − | 8 | t | − | 1 2 | t | × | 12 | + | 1 2 | t | × | 2 | t |
| = | 48 | − | 8 | t | − | 6 | t | + | 1 | t | t |
| = | 48 | − | 14 | t | + | 1 | t | t |
| 48 | − | 14 | t | + | 1 | t | t | = | 24 |