| ( | x | − | 5 | ) | ( | 50 | − | x | ) | − | x | ( | 45 | − | x | ) | = | 50 |
| Left side of the equation = | x | ( | 50 | − | x | ) | − | 5 | ( | 50 | − | x | ) | − | x | ( | 45 | − | x | ) |
| = | x | × | 50 | − | x | x | − | 5 | ( | 50 | − | x | ) | − | x | ( | 45 | − | x | ) |
| = | 50 | x | − | x | x | − | 5 | × | 50 | + | 5 | x | − | x | ( | 45 | − | x | ) |
| = | 50 | x | − | x | x | − | 250 | + | 5 | x | − | x | ( | 45 | − | x | ) |
| = | 55 | x | − | x | x | − | 250 | − | x | ( | 45 | − | x | ) |
| = | 55 | x | − | x | x | − | 250 | − | x | × | 45 | + | x | x |
| = | 10 | x | − | x | x | − | 250 | + | x | x |
| 10 | x | − | x | x | − | 250 | + | x | x | = | 50 |