| 6 | ( | x | − | 1800 | ) | = | 5 | ( | x | − | 1200 | ) |
| Left side of the equation = | 6 | x | − | 6 | × | 1800 |
| = | 6 | x | − | 10800 |
| 6 | x | − | 10800 | = | 5 | ( | x | − | 1200 | ) |
| Right side of the equation = | 5 | x | − | 5 | × | 1200 |
| = | 5 | x | − | 6000 |
| 6 | x | − | 10800 | = | 5 | x | − | 6000 |
| 6 | x | − | 5 | x | = | - | 6000 | + | 10800 |
| x | = | - | 6000 | + | 10800 |
| x | = | - | 6000 | + | 10800 |
| x | = | 4800 |