| ( | 100 | − | x | ) | × | 2 | = | ( | 150 | − | x | ) | × | 1 |
| Left side of the equation = | 100 | × | 2 | − | x | × | 2 |
| = | 200 | − | x | × | 2 |
| 200 | − | 2 | x | = | ( | 150 | − | x | ) | × | 1 |
| Right side of the equation = | 150 | × | 1 | − | x | × | 1 |
| = | 150 | − | x | × | 1 |
| 200 | − | 2 | x | = | 150 | − | 1 | x |
| - | 2 | x | + | 1 | x | = | 150 | − | 200 |
| - | x | = | 150 | − | 200 |
| - | x | = | 150 | − | 200 |
| - | x | = | - | 50 |
| 50 | = | x |
| x | = | 50 |