| ( | 53 | − | x | − | 8 | ) | ÷ | ( | x | + | 8 | ) | = | 13 | ÷ | 40 |
| Multiply both sides of the equation by: | ( | x | + | 8 | ) |
| ( | 53 | − | x | − | 8 | ) | = | 13 | ÷ | 40 | × | ( | x | + | 8 | ) |
| 53 | − | x | − | 8 | = | 13 | ÷ | 40 | × | ( | x | + | 8 | ) |
| 53 | − | x | − | 8 | = | 13 | ÷ | 40 | × | x | + | 13 | ÷ | 40 | × | 8 |
| 53 | − | x | − | 8 | = | 13 40 | x | + | 13 5 |
| 45 | − | x | = | 13 40 | x | + | 13 5 |
| - | x | − | 13 40 | x | = | 13 5 | − | 45 |
| - | 53 40 | x | = | 13 5 | − | 45 |
| - | 53 40 | x | = | - | 212 5 |
212 5 | = | 53 40 | x |
53 40 | x | = | 212 5 |
| x | = | 212 5 | ÷ | 53 40 |
| = | 212 5 | × | 40 53 |
| = | 4 | × | 8 |
| x | = | 32 |