| ( | x | − | 40 | ) | ( | 62 | − | 1 50 | x | ) | = | 6000 |
| 方程左边 = | x | ( | 62 | − | 1 50 | x | ) | − | 40 | ( | 62 | − | 1 50 | x | ) |
| = | x | × | 62 | − | x | × | 1 50 | x | − | 40 | ( | 62 | − | 1 50 | x | ) |
| = | 62 | x | − | x | × | 1 50 | x | − | 40 | × | 62 | + | 40 | × | 1 50 | x |
| = | 62 | x | − | x | × | 1 50 | x | − | 2480 | + | 4 5 | x |
| = | 314 5 | x | − | x | × | 1 50 | x | − | 2480 |
314 5 | x | − | x | × | 1 50 | x | − | 2480 | = | 6000 |