| - | 71810 | + | 60000 | + | x | − | ( | x | × | 5 200 | + | 330 | ) | − | 6300 | = | 3000 |
| 方程左边 = | - | 18110 | + | x | − | ( | x | × | 5 200 | + | 330 | ) |
| - | 18110 | + | x | − | ( | x | × | 5 200 | + | 330 | ) | = | 3000 |
| 方程左边 = | - | 18110 | + | x | − | x | × | 5 200 | − | 330 |
| = | - | 18440 | + | 39 40 | x |
| - | 18440 | + | 39 40 | x | = | 3000 |
39 40 | x | = | 3000 | + | 18440 |
39 40 | x | = | 21440 |
| x | = | 21440 | ÷ | 39 40 |
| = | 21440 | × | 40 39 |
| x | = | 857600 39 |
| x | = | 21989.74359 |