| ( | 24 | − | x | ) | ( | 25 | − | x | ) | = | x | ( | x | − | 9 | ) |
| Left side of the equation = | 24 | ( | 25 | − | x | ) | − | x | ( | 25 | − | x | ) |
| = | 24 | × | 25 | − | 24 | x | − | x | ( | 25 | − | x | ) |
| = | 600 | − | 24 | x | − | x | ( | 25 | − | x | ) |
| = | 600 | − | 24 | x | − | x | × | 25 | + | x | x |
| = | 600 | − | 49 | x | + | x | x |
| 600 | − | 49 | x | + | x | x | = | x | ( | x | − | 9 | ) |
| Right side of the equation = | x | x | − | x | × | 9 |
| 600 | − | 49 | x | + | x | x | = | x | x | − | 9 | x |