| 14 | ( | t | − | 56 | ) | = | 14 | ( | 80 | − | t | ) |
| 方程左边 = | 14 | t | − | 14 | × | 56 |
| = | 14 | t | − | 784 |
| 14 | t | − | 784 | = | 14 | ( | 80 | − | t | ) |
| 方程右边 = | 14 | × | 80 | − | 14 | t |
| = | 1120 | − | 14 | t |
| 14 | t | − | 784 | = | 1120 | − | 14 | t |
| 14 | t | + | 14 | t | = | 1120 | + | 784 |
| 28 | t | = | 1120 | + | 784 |
| 28 | t | = | 1904 |
| t | = | 1904 | ÷ | 28 |
| = | 1904 | × | 1 28 |
| = | 68 | × | 1 |
| t | = | 68 |