| 39 | ÷ | ( | 39 | − | x | ) | ÷ | 9 10 | = | 17 10 |
| 方程两边同时乘以: | ( | 39 | − | x | ) |
| 39 | ÷ | 9 10 | = | 17 10 | ( | 39 | − | x | ) |
| 39 | ÷ | 9 10 | = | 17 10 | × | 39 | − | 17 10 | x |
130 3 | = | 663 10 | − | 17 10 | x |
17 10 | x | = | 663 10 | − | 130 3 |
17 10 | x | = | 689 30 |
| x | = | 689 30 | ÷ | 17 10 |
| = | 689 30 | × | 10 17 |
| = | 689 3 | × | 1 17 |
| x | = | 689 51 |
| x | = | 13.509804 |