| ( | x | − | 20 | ) | ( | - | 10 | + | 500 | ) | = | 2000 |
| Left side of the equation = | x | ( | - | 10 | + | 500 | ) | − | 20 | ( | - | 10 | + | 500 | ) |
| = | - | x | × | 10 | + | x | × | 500 | − | 20 | ( | - | 10 | + | 500 | ) |
| = | 490 | x | − | 20 | ( | - | 10 | + | 500 | ) |
| = | 490 | x | + | 20 | × | 10 | − | 20 | × | 500 |
| = | 490 | x | + | 200 | − | 10000 |
| = | 490 | x | − | 9800 |
| 490 | x | − | 9800 | = | 2000 |
| 490 | x | = | 2000 | + | 9800 |
| 490 | x | = | 11800 |
| x | = | 11800 | ÷ | 490 |
| = | 11800 | × | 1 490 |
| = | 1180 | × | 1 49 |
| x | = | 1180 49 |
| x | = | 24.081633 |