| ( | 200 | − | x | ) | ( | 150 | − | x | ÷ | 2 | ) | = | 16610 |
| Left side of the equation = | 200 | ( | 150 | − | x | ÷ | 2 | ) | − | x | ( | 150 | − | x | ÷ | 2 | ) |
| = | 200 | × | 150 | − | 200 | x | ÷ | 2 | − | x | ( | 150 | − | x | ÷ | 2 | ) |
| = | 30000 | − | 100 | x | − | x | ( | 150 | − | x | ÷ | 2 | ) |
| = | 30000 | − | 100 | x | − | x | × | 150 | + | x | x | ÷ | 2 |
| = | 30000 | − | 250 | x | + | x | x | × | 1 2 |
| 30000 | − | 250 | x | + | x | x | × | 1 2 | = | 16610 |