| ( | 1 | − | 20 100 | ) | ( | 1 | + | x | ) | = | 1 |
| Left side of the equation = | 1 | ( | 1 | + | x | ) | − | 20 100 | ( | 1 | + | x | ) |
| = | 1 | × | 1 | + | 1 | x | − | 20 100 | ( | 1 | + | x | ) |
| = | 1 | + | 1 | x | − | 20 100 | ( | 1 | + | x | ) |
| = | 1 | + | 1 | x | − | 20 100 | × | 1 | − | 20 100 | x |
| = | 1 | + | 1 | x | − | 1 5 | − | 20 100 | x |
| = | 4 5 | + | 4 5 | x |
4 5 | + | 4 5 | x | = | 1 |
4 5 | x | = | 1 | − | 4 5 |
4 5 | x | = | 1 5 |
| x | = | 1 5 | ÷ | 4 5 |
| = | 1 5 | × | 5 4 |
| = | 1 | × | 1 4 |
| x | = | 1 4 |
| x | = | 0.25 |