| 15 | ( | 3 | x | − | 8 | ) | − | 4 | ( | 2 | x | + | 3 | ) | = | 25 | x | − | 24 |
| Left side of the equation = | 15 | × | 3 | x | − | 15 | × | 8 | − | 4 | ( | 2 | x | + | 3 | ) |
| = | 45 | x | − | 120 | − | 4 | ( | 2 | x | + | 3 | ) |
| = | 45 | x | − | 120 | − | 4 | × | 2 | x | − | 4 | × | 3 |
| = | 45 | x | − | 120 | − | 8 | x | − | 12 |
| = | 37 | x | − | 132 |
| 37 | x | − | 132 | = | 25 | x | − | 24 |
| 37 | x | − | 25 | x | = | - | 24 | + | 132 |
| 12 | x | = | - | 24 | + | 132 |
| 12 | x | = | 108 |
| x | = | 108 | ÷ | 12 |
| = | 108 | × | 1 12 |
| = | 9 | × | 1 |
| x | = | 9 |