| ( | 2 5 | + | x | ) | ÷ | ( | 1 5 | − | x | ) | = | 40 |
| Multiply both sides of the equation by: | ( | 1 5 | − | x | ) |
| ( | 2 5 | + | x | ) | = | 40 | ( | 1 5 | − | x | ) |
2 5 | + | x | = | 40 | ( | 1 5 | − | x | ) |
2 5 | + | x | = | 40 | × | 1 5 | − | 40 | x |
2 5 | + | x | = | 8 | − | 40 | x |
| x | + | 40 | x | = | 8 | − | 2 5 |
| 41 | x | = | 8 | − | 2 5 |
| 41 | x | = | 38 5 |
| x | = | 38 5 | ÷ | 41 |
| = | 38 5 | × | 1 41 |
| x | = | 38 205 |
| x | = | 0.185366 |