| ( | x | − | 42 | ) | ÷ | ( | 13 | ÷ | 25 | ) | = | ( | 3 | ÷ | 5 | ) | x | ÷ | ( | 12 | ÷ | 25 | ) |
| Multiply both sides of the equation by: | ( | 13 | ÷ | 25 | ) | , | ( | 12 | ÷ | 25 | ) |
| ( | x | − | 42 | ) | ( | 12 | ÷ | 25 | ) | = | ( | 3 | ÷ | 5 | ) | x | ( | 13 | ÷ | 25 | ) |
| x | ( | 12 | ÷ | 25 | ) | − | 42 | ( | 12 | ÷ | 25 | ) | = | ( | 3 | ÷ | 5 | ) | x | ( | 13 | ÷ | 25 | ) |
| x | ( | 12 | ÷ | 25 | ) | − | 42 | ( | 12 | ÷ | 25 | ) | = | 3 | ÷ | 5 | × | x | ( | 13 | ÷ | 25 | ) |
| x | ( | 12 | ÷ | 25 | ) | − | 42 | ( | 12 | ÷ | 25 | ) | = | 3 5 | x | ( | 13 | ÷ | 25 | ) |
| x | × | 12 | ÷ | 25 | − | 42 | ( | 12 | ÷ | 25 | ) | = | 3 5 | x | ( | 13 | ÷ | 25 | ) |
| x | × | 12 | ÷ | 25 | − | 42 | ( | 12 | ÷ | 25 | ) | = | 3 5 | x | × | 13 | ÷ | 25 |
| x | × | 12 25 | − | 42 | ( | 12 | ÷ | 25 | ) | = | 39 125 | x |
12 25 | x | − | 42 | × | 12 | ÷ | 25 | = | 39 125 | x |
12 25 | x | − | 504 25 | = | 39 125 | x |
12 25 | x | − | 39 125 | x | = | 504 25 |
21 125 | x | = | 504 25 |
| x | = | 504 25 | ÷ | 21 125 |
| = | 504 25 | × | 125 21 |
| = | 24 | × | 5 |
| x | = | 120 |