| ( | 2 5 | x | + | 9 10 | ) | ÷ | 1 2 | − | ( | 3 10 | + | 1 5 | x | ) | ÷ | 3 10 | = | ( | x | − | 5 | ) | ÷ | 2 |
| 方程左边 = | 2 5 | x | × | 2 | + | 9 10 | × | 2 | − | ( | 3 10 | + | 1 5 | x | ) | × | 10 3 |
| = | 4 5 | x | + | 9 5 | − | ( | 3 10 | + | 1 5 | x | ) | × | 10 3 |
| = | 4 5 | x | + | 9 5 | − | 3 10 | × | 10 3 | − | 1 5 | x | × | 10 3 |
| = | 4 5 | x | + | 9 5 | − | 1 | − | 2 3 | x |
| = | 2 15 | x | + | 4 5 |
2 15 | x | + | 4 5 | = | ( | x | − | 5 | ) | ÷ | 2 |
| 方程右边 = | x | × | 1 2 | − | 5 | × | 1 2 |
| = | x | × | 1 2 | − | 5 2 |
2 15 | x | + | 4 5 | = | 1 2 | x | − | 5 2 |
2 15 | x | − | 1 2 | x | = | - | 5 2 | − | 4 5 |
| - | 11 30 | x | = | - | 5 2 | − | 4 5 |
| - | 11 30 | x | = | - | 33 10 |
33 10 | = | 11 30 | x |
11 30 | x | = | 33 10 |
| x | = | 33 10 | ÷ | 11 30 |
| = | 33 10 | × | 30 11 |
| = | 3 | × | 3 |
| x | = | 9 |