125 200 | X | + | 75 100 | ( | 288 | − | X | ) | = | 200 |
| Left side of the equation = | 125 200 | X | + | 75 100 | × | 288 | − | 75 100 | X |
| = | 125 200 | X | + | 216 | − | 75 100 | X |
| = | - | 1 8 | X | + | 216 |
| - | 1 8 | X | + | 216 | = | 200 |
| - | 1 8 | X | = | 200 | − | 216 |
| - | 1 8 | X | = | - | 16 |
| 16 | = | 1 8 | X |
1 8 | X | = | 16 |
| X | = | 16 | ÷ | 1 8 |
| = | 16 | × | 8 |
| X | = | 128 |