| ( | 1 | − | x | ) | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) | = | 44 |
| 方程左边 = | 1 | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) | − | x | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) |
| = | 1 | × | 200 | + | 1 | × | 40 | ( | x | ÷ | 1 10 | ) | − | x | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) |
| = | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | − | x | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) |
| = | 200 | + | 40 | x | ÷ | 1 10 | − | x | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) |
| = | 200 | + | 400 | x | − | x | ( | 200 | + | 40 | ( | x | ÷ | 1 10 | ) | ) |
| = | 200 | + | 400 | x | − | x | × | 200 | − | x | × | 40 | ( | x | ÷ | 1 10 | ) |
| = | 200 | + | 200 | x | − | x | × | 40 | ( | x | ÷ | 1 10 | ) |
| = | 200 | + | 200 | x | − | x | × | 40 | x | ÷ | 1 10 |
| = | 200 | + | 200 | x | − | x | × | 400 | x |
| 200 | + | 200 | x | − | x | × | 400 | x | = | 44 |