| 5 | ÷ | 7 | × | ( | x | + | 39 | ) | = | 7 | ÷ | 11 | × | x | + | 39 |
| Left side of the equation = | 5 7 | ( | x | + | 39 | ) |
5 7 | ( | x | + | 39 | ) | = | 7 | ÷ | 11 | × | x | + | 39 |
| Left side of the equation = | 5 7 | x | + | 5 7 | × | 39 |
| = | 5 7 | x | + | 195 7 |
5 7 | x | + | 195 7 | = | 7 | ÷ | 11 | × | x | + | 39 |
| Right side of the equation = | 7 11 | x | + | 39 |
5 7 | x | + | 195 7 | = | 7 11 | x | + | 39 |
5 7 | x | − | 7 11 | x | = | 39 | − | 195 7 |
6 77 | x | = | 39 | − | 195 7 |
6 77 | x | = | 78 7 |
| x | = | 78 7 | ÷ | 6 77 |
| = | 78 7 | × | 77 6 |
| = | 13 | × | 11 |
| x | = | 143 |