547 100 | × | 100000 | = | 880 | × | 1 2 | ( | x | − | 20 | ) | + | 21 5 | × | 1000 | × | 5 2 | ( | x | − | 20 | ) |
| 方程左边 = | 547000 |
| 547000 | = | 880 | × | 1 2 | ( | x | − | 20 | ) | + | 21 5 | × | 1000 | × | 5 2 | ( | x | − | 20 | ) |
| 方程右边 = | 440 | ( | x | − | 20 | ) | + | 10500 | ( | x | − | 20 | ) |
| 547000 | = | 440 | ( | x | − | 20 | ) | + | 10500 | ( | x | − | 20 | ) |
| 方程右边 = | 440 | x | − | 440 | × | 20 | + | 10500 | ( | x | − | 20 | ) |
| = | 440 | x | − | 8800 | + | 10500 | ( | x | − | 20 | ) |
| = | 440 | x | − | 8800 | + | 10500 | x | − | 10500 | × | 20 |
| = | 440 | x | − | 8800 | + | 10500 | x | − | 210000 |
| = | 10940 | x | − | 218800 |
| 547000 | = | 10940 | x | − | 218800 |
| - | 10940 | x | = | - | 218800 | − | 547000 |
| - | 10940 | x | = | - | 765800 |
| 765800 | = | 10940 | x |
| 10940 | x | = | 765800 |
| x | = | 765800 | ÷ | 10940 |
| = | 765800 | × | 1 10940 |
| = | 38290 | × | 1 547 |
| x | = | 38290 547 |
| x | = | 70 |