| ( | x | − | 5 | ) | ( | 447 1000 | − | 3 200 | x | ) | = | ( | 10 | − | x | ) | ( | 17 1000 | x | + | 407 500 | ) |
| 方程左边 = | x | ( | 447 1000 | − | 3 200 | x | ) | − | 5 | ( | 447 1000 | − | 3 200 | x | ) |
| = | x | × | 447 1000 | − | x | × | 3 200 | x | − | 5 | ( | 447 1000 | − | 3 200 | x | ) |
| = | 447 1000 | x | − | x | × | 3 200 | x | − | 5 | × | 447 1000 | + | 5 | × | 3 200 | x |
| = | 447 1000 | x | − | x | × | 3 200 | x | − | 447 200 | + | 3 40 | x |
| = | 261 500 | x | − | x | × | 3 200 | x | − | 447 200 |
261 500 | x | − | x | × | 3 200 | x | − | 447 200 | = | ( | 10 | − | x | ) | ( | 17 1000 | x | + | 407 500 | ) |
| 方程右边 = | 10 | ( | 17 1000 | x | + | 407 500 | ) | − | x | ( | 17 1000 | x | + | 407 500 | ) |
| = | 10 | × | 17 1000 | x | + | 10 | × | 407 500 | − | x | ( | 17 1000 | x | + | 407 500 | ) |
| = | 17 100 | x | + | 407 50 | − | x | ( | 17 1000 | x | + | 407 500 | ) |
| = | 17 100 | x | + | 407 50 | − | x | × | 17 1000 | x | − | x | × | 407 500 |
| = | - | 161 250 | x | + | 407 50 | − | x | × | 17 1000 | x |
261 500 | x | − | x | × | 3 200 | x | − | 447 200 | = | - | 161 250 | x | + | 407 50 | − | x | × | 17 1000 | x |