| ( | x | − | 240 | ) | × | 8 | = | ( | x | − | 340 | ) | × | 9 |
| Left side of the equation = | x | × | 8 | − | 240 | × | 8 |
| = | x | × | 8 | − | 1920 |
| 8 | x | − | 1920 | = | ( | x | − | 340 | ) | × | 9 |
| Right side of the equation = | x | × | 9 | − | 340 | × | 9 |
| = | x | × | 9 | − | 3060 |
| 8 | x | − | 1920 | = | 9 | x | − | 3060 |
| 8 | x | − | 9 | x | = | - | 3060 | + | 1920 |
| - | x | = | - | 3060 | + | 1920 |
| - | x | = | - | 3060 | + | 1920 |
| - | x | = | - | 1140 |
| 1140 | = | x |
| x | = | 1140 |