| ( | 50 | + | 49 | x | ) | − | 9900 | ( | 50 | − | 49 | x | ) | − | 98 | ( | 50 | − | 49 | x | ) | ( | 50 | + | 49 | x | ) | = | 0 |
| 方程左边 = | 50 | + | 49 | x | − | 9900 | ( | 50 | − | 49 | x | ) | − | 98 | ( | 50 | − | 49 | x | ) | ( | 50 | + | 49 | x | ) |
| = | 50 | + | 49 | x | − | 9900 | × | 50 | + | 9900 | × | 49 | x | − | 98 | ( | 50 | − | 49 | x | ) | ( | 50 | + | 49 | x | ) |
| = | 50 | + | 49 | x | − | 495000 | + | 485100 | x | − | 98 | ( | 50 | − | 49 | x | ) | ( | 50 | + | 49 | x | ) |
| = | - | 494950 | + | 485149 | x | − | 98 | ( | 50 | − | 49 | x | ) | ( | 50 | + | 49 | x | ) |
| = | - | 494950 | + | 485149 | x | − | 98 | × | 50 | ( | 50 | + | 49 | x | ) | + | 98 | × | 49 | x | ( | 50 | + | 49 | x | ) |
| = | - | 494950 | + | 485149 | x | − | 4900 | ( | 50 | + | 49 | x | ) | + | 4802 | x | ( | 50 | + | 49 | x | ) |
| = | - | 494950 | + | 485149 | x | − | 4900 | × | 50 | − | 4900 | × | 49 | x | + | 4802 | x | ( | 50 | + | 49 | x | ) |
| = | - | 494950 | + | 485149 | x | − | 245000 | − | 240100 | x | + | 4802 | x | ( | 50 | + | 49 | x | ) |
| = | - | 739950 | + | 245049 | x | + | 4802 | x | ( | 50 | + | 49 | x | ) |
| = | - | 739950 | + | 245049 | x | + | 4802 | x | × | 50 | + | 4802 | x | × | 49 | x |
| = | - | 739950 | + | 245049 | x | + | 240100 | x | + | 235298 | x | x |
| = | - | 739950 | + | 485149 | x | + | 235298 | x | x |
| - | 739950 | + | 485149 | x | + | 235298 | x | x | = | 0 |