| 15 | ÷ | ( | x | + | 45 | ) | = | 30 100 |
| Multiply both sides of the equation by: | ( | x | + | 45 | ) |
| 15 | = | 30 100 | ( | x | + | 45 | ) |
| 15 | = | 30 100 | x | + | 30 100 | × | 45 |
| 15 | = | 30 100 | x | + | 27 2 |
| - | 30 100 | x | = | 27 2 | − | 15 |
| - | 30 100 | x | = | - | 3 2 |
3 2 | = | 30 100 | x |
30 100 | x | = | 3 2 |
| x | = | 3 2 | ÷ | 30 100 |
| = | 3 2 | × | 100 30 |
| = | 1 | × | 50 10 |
| x | = | 50 10 |
| x | = | 5 |