| ( | 16 | X | ) | ÷ | 2 | = | ( | 10 | ( | 85 | − | X | ) | ) | ÷ | 3 |
| 方程左边 = | 16 | X | × | 1 2 |
| = | 8 | X |
| 8 | X | = | ( | 10 | ( | 85 | − | X | ) | ) | ÷ | 3 |
| 方程右边 = | 10 | ( | 85 | − | X | ) | × | 1 3 |
| = | 10 3 | ( | 85 | − | X | ) |
| = | 10 3 | × | 85 | − | 10 3 | X |
| = | 850 3 | − | 10 3 | X |
| 8 | X | = | 850 3 | − | 10 3 | X |
| 8 | X | + | 10 3 | X | = | 850 3 |
34 3 | X | = | 850 3 |
| X | = | 850 3 | ÷ | 34 3 |
| = | 850 3 | × | 3 34 |
| = | 25 | × | 1 |
| X | = | 25 |