| 7 | x | − | 392 25 | = | 21 10 | ( | x | + | 14 5 | ) |
| 方程右边 = | 21 10 | x | + | 21 10 | × | 14 5 |
| = | 21 10 | x | + | 147 25 |
| 7 | x | − | 392 25 | = | 21 10 | x | + | 147 25 |
| 7 | x | − | 21 10 | x | = | 147 25 | + | 392 25 |
49 10 | x | = | 147 25 | + | 392 25 |
49 10 | x | = | 539 25 |
| x | = | 539 25 | ÷ | 49 10 |
| = | 539 25 | × | 10 49 |
| = | 11 5 | × | 2 |
| x | = | 22 5 |
| x | = | 4.4 |