| 1000 | ( | 500 | + | X | ) | = | ( | 1000 | + | 100 | ) | ( | 500 | − | X | ) |
| Left side of the equation = | 1000 | × | 500 | + | 1000 | X |
| = | 500000 | + | 1000 | X |
| 500000 | + | 1000 | X | = | ( | 1000 | + | 100 | ) | ( | 500 | − | X | ) |
| Right side of the equation = | 1000 | ( | 500 | − | X | ) | + | 100 | ( | 500 | − | X | ) |
| = | 1000 | × | 500 | − | 1000 | X | + | 100 | ( | 500 | − | X | ) |
| = | 500000 | − | 1000 | X | + | 100 | ( | 500 | − | X | ) |
| = | 500000 | − | 1000 | X | + | 100 | × | 500 | − | 100 | X |
| = | 500000 | − | 1000 | X | + | 50000 | − | 100 | X |
| = | 550000 | − | 1100 | X |
| 500000 | + | 1000 | X | = | 550000 | − | 1100 | X |
| 1000 | X | + | 1100 | X | = | 550000 | − | 500000 |
| 2100 | X | = | 550000 | − | 500000 |
| 2100 | X | = | 50000 |
| X | = | 50000 | ÷ | 2100 |
| = | 50000 | × | 1 2100 |
| = | 500 | × | 1 21 |
| X | = | 500 21 |
| X | = | 23.809524 |