1 2 | ( | 5 | − | 2 | t | ) | × | 3 5 | ( | 4 | − | t | ) | = | 0 |
| 方程左边 = | 3 10 | ( | 5 | − | 2 | t | ) | ( | 4 | − | t | ) |
3 10 | ( | 5 | − | 2 | t | ) | ( | 4 | − | t | ) | = | 0 |
| 方程左边 = | 3 10 | × | 5 | ( | 4 | − | t | ) | − | 3 10 | × | 2 | t | ( | 4 | − | t | ) |
| = | 3 2 | ( | 4 | − | t | ) | − | 3 5 | t | ( | 4 | − | t | ) |
| = | 3 2 | × | 4 | − | 3 2 | t | − | 3 5 | t | ( | 4 | − | t | ) |
| = | 6 | − | 3 2 | t | − | 3 5 | t | ( | 4 | − | t | ) |
| = | 6 | − | 3 2 | t | − | 3 5 | t | × | 4 | + | 3 5 | t | t |
| = | 6 | − | 3 2 | t | − | 12 5 | t | + | 3 5 | t | t |
| = | 6 | − | 39 10 | t | + | 3 5 | t | t |
| 6 | − | 39 10 | t | + | 3 5 | t | t | = | 0 |
| t1= | 5 2 |
| t2=4 |