7 20 | ( | 500 | − | x | ) | − | 5 2 | x | = | 150 |
| Left side of the equation = | 7 20 | × | 500 | − | 7 20 | x | − | 5 2 | x |
| = | 175 | − | 7 20 | x | − | 5 2 | x |
| = | 175 | − | 57 20 | x |
| 175 | − | 57 20 | x | = | 150 |
| - | 57 20 | x | = | 150 | − | 175 |
| - | 57 20 | x | = | - | 25 |
| 25 | = | 57 20 | x |
57 20 | x | = | 25 |
| x | = | 25 | ÷ | 57 20 |
| = | 25 | × | 20 57 |
| x | = | 500 57 |
| x | = | 8.77193 |