| 15 | − | ( | 7 | − | 5 | X | ) | = | 2 | X | + | ( | 5 | − | 3 | X | ) |
| Left side of the equation = | 15 | − | 7 | + | 5 | X |
| = | 8 | + | 5 | X |
| 8 | + | 5 | X | = | 2 | X | + | ( | 5 | − | 3 | X | ) |
| Right side of the equation = | 2 | X | + | 5 | − | 3 | X |
| = | - | 1 | X | + | 5 |
| 8 | + | 5 | X | = | - | 1 | X | + | 5 |
| 5 | X | + | 1 | X | = | 5 | − | 8 |
| 6 | X | = | 5 | − | 8 |
| 6 | X | = | - | 3 |
| X | = | - | 3 | ÷ | 6 |
| = | - | 3 | × | 1 6 |
| = | - | 1 | × | 1 2 |
| X | = | - | 1 2 |
| X | = | - 0.5 |