| 5 | − | 7 | ( | 17 | − | 3 | ( | 17 | − | 2 | x | ) | ) | = | - | 9 | ( | 7 | x | + | 8 | ) |
| Left side of the equation = | 5 | − | 7 | × | 17 | + | 7 | × | 3 | ( | 17 | − | 2 | x | ) |
| = | 5 | − | 119 | + | 21 | ( | 17 | − | 2 | x | ) |
| = | - | 114 | + | 21 | ( | 17 | − | 2 | x | ) |
| = | - | 114 | + | 21 | × | 17 | − | 21 | × | 2 | x |
| = | - | 114 | + | 357 | − | 42 | x |
| = | 243 | − | 42 | x |
| 243 | − | 42 | x | = | - | 9 | ( | 7 | x | + | 8 | ) |
| Right side of the equation = | - | 9 | × | 7 | x | − | 9 | × | 8 |
| = | - | 63 | x | − | 72 |
| 243 | − | 42 | x | = | - | 63 | x | − | 72 |
| - | 42 | x | + | 63 | x | = | - | 72 | − | 243 |
| 21 | x | = | - | 72 | − | 243 |
| 21 | x | = | - | 315 |
| x | = | - | 315 | ÷ | 21 |
| = | - | 315 | × | 1 21 |
| = | - | 15 | × | 1 |
| x | = | - | 15 |