| ( | x | − | 2 | ) | ( | 60 | − | x | − | 2 | ) | = | 600 |
| Left side of the equation = | x | ( | 60 | − | x | − | 2 | ) | − | 2 | ( | 60 | − | x | − | 2 | ) |
| = | x | × | 60 | − | x | x | − | x | × | 2 | − | 2 | ( | 60 | − | x | − | 2 | ) |
| = | 58 | x | − | x | x | − | 2 | ( | 60 | − | x | − | 2 | ) |
| = | 58 | x | − | x | x | − | 2 | × | 60 | + | 2 | x | + | 2 | × | 2 |
| = | 58 | x | − | x | x | − | 120 | + | 2 | x | + | 4 |
| = | 60 | x | − | x | x | − | 116 |
| 60 | x | − | x | x | − | 116 | = | 600 |