| ( | 2 | x | + | 1 | ) | ( | x | − | 2 | ) | = | 5 | − | 3 | x |
| Left side of the equation = | 2 | x | ( | x | − | 2 | ) | + | 1 | ( | x | − | 2 | ) |
| = | 2 | x | x | − | 2 | x | × | 2 | + | 1 | ( | x | − | 2 | ) |
| = | 2 | x | x | − | 4 | x | + | 1 | ( | x | − | 2 | ) |
| = | 2 | x | x | − | 4 | x | + | 1 | x | − | 1 | × | 2 |
| = | 2 | x | x | − | 4 | x | + | 1 | x | − | 2 |
| = | 2 | x | x | − | 3 | x | − | 2 |
| 2 | x | x | − | 3 | x | − | 2 | = | 5 | − | 3 | x |
| x1= | - | √7 √2 |
| x2= | √7 √2 |