| 2500 | ( | x | + | 2 | ) | = | 2 | x | ( | x | + | 22 | ) | × | 1800 | x |
| 方程左边 = | 2500 | x | + | 2500 | × | 2 |
| = | 2500 | x | + | 5000 |
| 2500 | x | + | 5000 | = | 2 | x | ( | x | + | 22 | ) | × | 1800 | x |
| 方程右边 = | 3600 | x | ( | x | + | 22 | ) | x |
| 2500 | x | + | 5000 | = | 3600 | x | ( | x | + | 22 | ) | x |
| 方程右边 = | 3600 | x | x | x | + | 3600 | x | × | 22 | x |
| = | 3600 | x | x | x | + | 79200 | x | x |
| 2500 | x | + | 5000 | = | 3600 | x | x | x | + | 79200 | x | x |