69 20 | × | 10 | × | 10 | × | 10 | × | 10 | × | 10 | × | 10 | = | 48 5 | × | 1000 | x | ( | 60 | − | x | ÷ | 2 | ) |
| 方程左边 = | 3450000 |
| 3450000 | = | 48 5 | × | 1000 | x | ( | 60 | − | x | ÷ | 2 | ) |
| 方程右边 = | 9600 | x | ( | 60 | − | x | ÷ | 2 | ) |
| 3450000 | = | 9600 | x | ( | 60 | − | x | ÷ | 2 | ) |
| 方程右边 = | 9600 | x | × | 60 | − | 9600 | x | x | ÷ | 2 |
| = | 576000 | x | − | 4800 | x | x |
| 3450000 | = | 576000 | x | − | 4800 | x | x |