18 25 | = | 36 | ÷ | ( | 100 | − | 10 | − | x | ) |
| Multiply both sides of the equation by: | ( | 100 | − | 10 | − | x | ) |
18 25 | ( | 100 | − | 10 | − | x | ) | = | 36 |
18 25 | × | 100 | − | 18 25 | × | 10 | − | 18 25 | x | = | 36 |
| 72 | − | 36 5 | − | 18 25 | x | = | 36 |
324 5 | − | 18 25 | x | = | 36 |
| - | 18 25 | x | = | 36 | − | 324 5 |
| - | 18 25 | x | = | - | 144 5 |
144 5 | = | 18 25 | x |
18 25 | x | = | 144 5 |
| x | = | 144 5 | ÷ | 18 25 |
| = | 144 5 | × | 25 18 |
| = | 8 | × | 5 |
| x | = | 40 |