| ( | x | − | 40 | ) | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) | = | 5600 |
| 方程左边 = | x | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) | − | 40 | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) |
| = | x | × | 150 | − | x | × | 5 | x | − | x | × | 60 | ÷ | 10 | − | 40 | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) |
| = | x | × | 150 | − | x | × | 5 | x | − | x | × | 6 | − | 40 | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) |
| = | 144 | x | − | x | × | 5 | x | − | 40 | ( | 150 | − | 5 | x | − | 60 | ÷ | 10 | ) |
| = | 144 | x | − | x | × | 5 | x | − | 40 | × | 150 | + | 40 | × | 5 | x | + | 40 | × | 60 |
| = | 144 | x | − | x | × | 5 | x | − | 6000 | + | 200 | x | + | 240 |
| = | 344 | x | − | x | × | 5 | x | − | 5760 |
| 344 | x | − | x | × | 5 | x | − | 5760 | = | 5600 |