| 2 | ( | 10 | ( | 10 | − | x | ) | + | x | ) | − | 1 | = | 10 | x | + | ( | 10 | − | x | ) |
| Left side of the equation = | 2 | × | 10 | ( | 10 | − | x | ) | + | 2 | x | − | 1 |
| = | 20 | ( | 10 | − | x | ) | + | 2 | x | − | 1 |
| = | 20 | × | 10 | − | 20 | x | + | 2 | x | − | 1 |
| = | 200 | − | 20 | x | + | 2 | x | − | 1 |
| = | 199 | − | 18 | x |
| 199 | − | 18 | x | = | 10 | x | + | ( | 10 | − | x | ) |
| Right side of the equation = | 10 | x | + | 10 | − | x |
| = | 9 | x | + | 10 |
| 199 | − | 18 | x | = | 9 | x | + | 10 |
| - | 18 | x | − | 9 | x | = | 10 | − | 199 |
| - | 27 | x | = | 10 | − | 199 |
| - | 27 | x | = | - | 189 |
| 189 | = | 27 | x |
| 27 | x | = | 189 |
| x | = | 189 | ÷ | 27 |
| = | 189 | × | 1 27 |
| = | 7 | × | 1 |
| x | = | 7 |