| 66 | x | + | 17 | ( | 1200 | − | 25 | x | ) | = | 3967 |
| 方程左边 = | 66 | x | + | 17 | × | 1200 | − | 17 | × | 25 | x |
| = | 66 | x | + | 20400 | − | 425 | x |
| = | - | 359 | x | + | 20400 |
| - | 359 | x | + | 20400 | = | 3967 |
| - | 359 | x | = | 3967 | − | 20400 |
| - | 359 | x | = | - | 16433 |
| 16433 | = | 359 | x |
| 359 | x | = | 16433 |
| x | = | 16433 | ÷ | 359 |
| = | 16433 | × | 1 359 |
| x | = | 16433 359 |
| x | = | 45.774373 |