| 9 | ( | 80 | − | t | ) | = | 15 | ( | t | − | 56 | ) |
| Left side of the equation = | 9 | × | 80 | − | 9 | t |
| = | 720 | − | 9 | t |
| 720 | − | 9 | t | = | 15 | ( | t | − | 56 | ) |
| Right side of the equation = | 15 | t | − | 15 | × | 56 |
| = | 15 | t | − | 840 |
| 720 | − | 9 | t | = | 15 | t | − | 840 |
| - | 9 | t | − | 15 | t | = | - | 840 | − | 720 |
| - | 24 | t | = | - | 840 | − | 720 |
| - | 24 | t | = | - | 1560 |
| 1560 | = | 24 | t |
| 24 | t | = | 1560 |
| t | = | 1560 | ÷ | 24 |
| = | 1560 | × | 1 24 |
| = | 65 | × | 1 |
| t | = | 65 |