| 600 | + | 100 | x | = | 200 | ( | x | − | 6 | ) |
| Right side of the equation = | 200 | x | − | 200 | × | 6 |
| = | 200 | x | − | 1200 |
| 600 | + | 100 | x | = | 200 | x | − | 1200 |
| 100 | x | − | 200 | x | = | - | 1200 | − | 600 |
| - | 100 | x | = | - | 1200 | − | 600 |
| - | 100 | x | = | - | 1800 |
| 1800 | = | 100 | x |
| 100 | x | = | 1800 |
| x | = | 1800 | ÷ | 100 |
| = | 1800 | × | 1 100 |
| = | 18 | × | 1 |
| x | = | 18 |