| ( | 129 | ( | 1 | + | 20 100 | ) | ) | + | ( | 3 100 | x | ) | = | x |
| Left side of the equation = | 129 | ( | 1 | + | 20 100 | ) | + | ( | 3 100 | x | ) |
| = | 129 | × | 1 | + | 129 | × | 20 100 | + | ( | 3 100 | x | ) |
| = | 129 | + | 129 5 | + | ( | 3 100 | x | ) |
| = | 774 5 | + | ( | 3 100 | x | ) |
| = | 774 5 | + | 3 100 | x |
774 5 | + | 3 100 | x | = | x |
3 100 | x | − | x | = | - | 774 5 |
| - | 97 100 | x | = | - | 774 5 |
774 5 | = | 97 100 | x |
97 100 | x | = | 774 5 |
| x | = | 774 5 | ÷ | 97 100 |
| = | 774 5 | × | 100 97 |
| = | 774 | × | 20 97 |
| x | = | 15480 97 |
| x | = | 159.587629 |