| ( | 4120 | + | 90 | x | ) | ÷ | ( | 97 2 | + | x | ) | = | 88 |
| Multiply both sides of the equation by: | ( | 97 2 | + | x | ) |
| ( | 4120 | + | 90 | x | ) | = | 88 | ( | 97 2 | + | x | ) |
| 4120 | + | 90 | x | = | 88 | ( | 97 2 | + | x | ) |
| 4120 | + | 90 | x | = | 88 | × | 97 2 | + | 88 | x |
| 4120 | + | 90 | x | = | 4268 | + | 88 | x |
| 90 | x | − | 88 | x | = | 4268 | − | 4120 |
| 2 | x | = | 4268 | − | 4120 |
| 2 | x | = | 148 |
| x | = | 148 | ÷ | 2 |
| = | 148 | × | 1 2 |
| = | 74 | × | 1 |
| x | = | 74 |