| ( | 18000 | + | 8600 | X | ) | ÷ | 2 | = | 66000 | + | 8600 | X | − | 2417 | × | 10 |
| Left side of the equation = | 18000 | × | 1 2 | + | 8600 | X | × | 1 2 |
| = | 9000 | + | 4300 | X |
| 9000 | + | 4300 | X | = | 66000 | + | 8600 | X | − | 2417 | × | 10 |
| Right side of the equation = | 66000 | + | 8600 | X | − | 24170 |
| = | 41830 | + | 8600 | X |
| 9000 | + | 4300 | X | = | 41830 | + | 8600 | X |
| 4300 | X | − | 8600 | X | = | 41830 | − | 9000 |
| - | 4300 | X | = | 41830 | − | 9000 |
| - | 4300 | X | = | 32830 |
| - | 32830 | = | 4300 | X |
| 4300 | X | = | - | 32830 |
| X | = | - | 32830 | ÷ | 4300 |
| = | - | 32830 | × | 1 4300 |
| = | - | 3283 | × | 1 430 |
| X | = | - | 3283 430 |
| X | = | - 7.634884 |