| ( | 60 | − | x | ÷ | 10 | ) | ( | 140 | + | x | ) | = | 10080 |
| Left side of the equation = | 60 | ( | 140 | + | x | ) | − | x | ÷ | 10 | × | ( | 140 | + | x | ) |
| = | 60 | × | 140 | + | 60 | x | − | x | × | 1 10 | ( | 140 | + | x | ) |
| = | 8400 | + | 60 | x | − | x | × | 1 10 | ( | 140 | + | x | ) |
| = | 8400 | + | 60 | x | − | x | × | 1 10 | × | 140 | − | x | × | 1 10 | x |
| = | 8400 | + | 60 | x | − | x | × | 14 | − | x | × | 1 10 | x |
| = | 8400 | + | 46 | x | − | x | × | 1 10 | x |
| 8400 | + | 46 | x | − | x | × | 1 10 | x | = | 10080 |