| ( | x | − | 50 | ) | ( | 1100 | − | 10 | x | ) | = | 8000 |
| Left side of the equation = | x | ( | 1100 | − | 10 | x | ) | − | 50 | ( | 1100 | − | 10 | x | ) |
| = | x | × | 1100 | − | x | × | 10 | x | − | 50 | ( | 1100 | − | 10 | x | ) |
| = | 1100 | x | − | x | × | 10 | x | − | 50 | × | 1100 | + | 50 | × | 10 | x |
| = | 1100 | x | − | x | × | 10 | x | − | 55000 | + | 500 | x |
| = | 1600 | x | − | x | × | 10 | x | − | 55000 |
| 1600 | x | − | x | × | 10 | x | − | 55000 | = | 8000 |