| 2 | ( | 3 10 | x | − | 4 | ) | − | 5 | ( | 1 5 | x | + | 3 | ) | = | 9 |
| Left side of the equation = | 2 | × | 3 10 | x | − | 2 | × | 4 | − | 5 | ( | 1 5 | x | + | 3 | ) |
| = | 3 5 | x | − | 8 | − | 5 | ( | 1 5 | x | + | 3 | ) |
| = | 3 5 | x | − | 8 | − | 5 | × | 1 5 | x | − | 5 | × | 3 |
| = | 3 5 | x | − | 8 | − | 1 | x | − | 15 |
| = | - | 2 5 | x | − | 23 |
| - | 2 5 | x | − | 23 | = | 9 |
| - | 2 5 | x | = | 9 | + | 23 |
| - | 2 5 | x | = | 32 |
| - | 32 | = | 2 5 | x |
2 5 | x | = | - | 32 |
| x | = | - | 32 | ÷ | 2 5 |
| = | - | 32 | × | 5 2 |
| = | - | 16 | × | 5 |
| x | = | - | 80 |