| ( | x | − | 1 | ) | ( | x | − | 2 | ) | = | - | 4 | ÷ | 9 |
| Left side of the equation = | x | ( | x | − | 2 | ) | − | 1 | ( | x | − | 2 | ) |
| = | x | x | − | x | × | 2 | − | 1 | ( | x | − | 2 | ) |
| = | x | x | − | 2 | x | − | 1 | x | + | 1 | × | 2 |
| = | x | x | − | 2 | x | − | 1 | x | + | 2 |
| = | x | x | − | 3 | x | + | 2 |
| x | x | − | 3 | x | + | 2 | = | - | 4 | ÷ | 9 |
| Right side of the equation = | - | 4 9 |
| x | x | − | 3 | x | + | 2 | = | - | 4 9 |