| ( | 5 | x | − | 25 | ) | ÷ | ( | 4 | x | + | 25 | ) | = | 5 | ÷ | 7 |
| Multiply both sides of the equation by: | ( | 4 | x | + | 25 | ) |
| ( | 5 | x | − | 25 | ) | = | 5 | ÷ | 7 | × | ( | 4 | x | + | 25 | ) |
| 5 | x | − | 25 | = | 5 | ÷ | 7 | × | ( | 4 | x | + | 25 | ) |
| 5 | x | − | 25 | = | 5 | ÷ | 7 | × | 4 | x | + | 5 | ÷ | 7 | × | 25 |
| 5 | x | − | 25 | = | 20 7 | x | + | 125 7 |
| 5 | x | − | 20 7 | x | = | 125 7 | + | 25 |
15 7 | x | = | 125 7 | + | 25 |
15 7 | x | = | 300 7 |
| x | = | 300 7 | ÷ | 15 7 |
| = | 300 7 | × | 7 15 |
| = | 20 | × | 1 |
| x | = | 20 |