| ( | x | + | 2 | − | 3 | ) | × | 2 | × | 17 20 | = | 40 |
| 方程左边 = | ( | x | + | 2 | − | 3 | ) | × | 17 10 |
| ( | x | + | 2 | − | 3 | ) | × | 17 10 | = | 40 |
| 方程左边 = | x | × | 17 10 | + | 2 | × | 17 10 | − | 3 | × | 17 10 |
| = | x | × | 17 10 | + | 17 5 | − | 51 10 |
| = | 17 10 | x | − | 17 10 |
17 10 | x | − | 17 10 | = | 40 |
17 10 | x | = | 40 | + | 17 10 |
17 10 | x | = | 417 10 |
| x | = | 417 10 | ÷ | 17 10 |
| = | 417 10 | × | 10 17 |
| = | 417 | × | 1 17 |
| x | = | 417 17 |
| x | = | 24.529412 |