| 3 | x | + | 4 | ( | ( | 28 | − | 5 | x | ) | ÷ | 6 | ) | = | 18 |
| Left side of the equation = | 3 | x | + | 4 | ( | 28 | − | 5 | x | ) | ÷ | 6 |
| = | 3 | x | + | 2 3 | ( | 28 | − | 5 | x | ) |
| = | 3 | x | + | 2 3 | × | 28 | − | 2 3 | × | 5 | x |
| = | 3 | x | + | 56 3 | − | 10 3 | x |
| = | - | 1 3 | x | + | 56 3 |
| - | 1 3 | x | + | 56 3 | = | 18 |
| - | 1 3 | x | = | 18 | − | 56 3 |
| - | 1 3 | x | = | - | 2 3 |
2 3 | = | 1 3 | x |
1 3 | x | = | 2 3 |
| x | = | 2 3 | ÷ | 1 3 |
| = | 2 3 | × | 3 |
| = | 2 | × | 1 |
| x | = | 2 |