| ( | 2 | x | + | 1 | ) | ( | x | − | 1 | ) | = | 8 | ( | 9 | − | x | ) | − | 1 |
| Left side of the equation = | 2 | x | ( | x | − | 1 | ) | + | 1 | ( | x | − | 1 | ) |
| = | 2 | x | x | − | 2 | x | × | 1 | + | 1 | ( | x | − | 1 | ) |
| = | 2 | x | x | − | 2 | x | + | 1 | ( | x | − | 1 | ) |
| = | 2 | x | x | − | 2 | x | + | 1 | x | − | 1 | × | 1 |
| = | 2 | x | x | − | 2 | x | + | 1 | x | − | 1 |
| = | 2 | x | x | − | 1 | x | − | 1 |
| 2 | x | x | − | 1 | x | − | 1 | = | 8 | ( | 9 | − | x | ) | − | 1 |
| Right side of the equation = | 8 | × | 9 | − | 8 | x | − | 1 |
| = | 72 | − | 8 | x | − | 1 |
| = | 71 | − | 8 | x |
| 2 | x | x | − | 1 | x | − | 1 | = | 71 | − | 8 | x |
| x2= | 9 2 |