| 280 | × | 80 | ÷ | 2 | × | 5 | ÷ | 6 | = | ( | - | 4 | x | + | 280 | ) | ( | 80 | − | x | ) |
| Left side of the equation = | 28000 3 |
28000 3 | = | ( | - | 4 | x | + | 280 | ) | ( | 80 | − | x | ) |
| Right side of the equation = | - | 4 | x | ( | 80 | − | x | ) | + | 280 | ( | 80 | − | x | ) |
| = | - | 4 | x | × | 80 | + | 4 | x | x | + | 280 | ( | 80 | − | x | ) |
| = | - | 320 | x | + | 4 | x | x | + | 280 | ( | 80 | − | x | ) |
| = | - | 320 | x | + | 4 | x | x | + | 280 | × | 80 | − | 280 | x |
| = | - | 320 | x | + | 4 | x | x | + | 22400 | − | 280 | x |
| = | - | 600 | x | + | 4 | x | x | + | 22400 |
28000 3 | = | - | 600 | x | + | 4 | x | x | + | 22400 |