| ( | 68 | + | x | ) | ÷ | ( | 20 | + | x | ) | = | 3 |
| Multiply both sides of the equation by: | ( | 20 | + | x | ) |
| ( | 68 | + | x | ) | = | 3 | ( | 20 | + | x | ) |
| 68 | + | x | = | 3 | ( | 20 | + | x | ) |
| 68 | + | x | = | 3 | × | 20 | + | 3 | x |
| 68 | + | x | = | 60 | + | 3 | x |
| x | − | 3 | x | = | 60 | − | 68 |
| - | 2 | x | = | 60 | − | 68 |
| - | 2 | x | = | - | 8 |
| 8 | = | 2 | x |
| 2 | x | = | 8 |
| x | = | 8 | ÷ | 2 |
| = | 8 | × | 1 2 |
| = | 4 | × | 1 |
| x | = | 4 |