| 20 | × | 5 | + | ( | 20 | − | x | ) | ( | - | 3 | ) | = | 68 |
| Left side of the equation = | 100 | + | ( | 20 | − | x | ) | ( | - | 3 | ) |
| 100 | + | ( | 20 | − | x | ) | ( | - | 3 | ) | = | 68 |
| Left side of the equation = | 100 | + | 20 | ( | - | 3 | ) | − | x | ( | - | 3 | ) |
| = | 100 | − | 20 | × | 3 | − | x | ( | - | 3 | ) |
| = | 100 | − | 60 | − | x | ( | - | 3 | ) |
| = | 40 | − | x | ( | - | 3 | ) |
| = | 40 | + | x | × | 3 |
| 40 | + | 3 | x | = | 68 |
| 3 | x | = | 68 | − | 40 |
| 3 | x | = | 28 |
| x | = | 28 | ÷ | 3 |
| = | 28 | × | 1 3 |
| x | = | 28 3 |
| x | = | 9.333333 |