| ( | x | − | 55 | ) | ( | 540 | − | 4 | x | ) | = | 6300 |
| Left side of the equation = | x | ( | 540 | − | 4 | x | ) | − | 55 | ( | 540 | − | 4 | x | ) |
| = | x | × | 540 | − | x | × | 4 | x | − | 55 | ( | 540 | − | 4 | x | ) |
| = | 540 | x | − | x | × | 4 | x | − | 55 | × | 540 | + | 55 | × | 4 | x |
| = | 540 | x | − | x | × | 4 | x | − | 29700 | + | 220 | x |
| = | 760 | x | − | x | × | 4 | x | − | 29700 |
| 760 | x | − | x | × | 4 | x | − | 29700 | = | 6300 |