| - | 9 | + | 6 | ( | - | 1 | − | 5 | ( | - | 8 | − | x | ) | ) | = | 9 | ( | x | + | 4 | ) |
| Left side of the equation = | - | 9 | − | 6 | × | 1 | − | 6 | × | 5 | ( | - | 8 | − | x | ) |
| = | - | 9 | − | 6 | − | 30 | ( | - | 8 | − | x | ) |
| = | - | 15 | − | 30 | ( | - | 8 | − | x | ) |
| = | - | 15 | + | 30 | × | 8 | + | 30 | x |
| = | - | 15 | + | 240 | + | 30 | x |
| = | 225 | + | 30 | x |
| 225 | + | 30 | x | = | 9 | ( | x | + | 4 | ) |
| Right side of the equation = | 9 | x | + | 9 | × | 4 |
| = | 9 | x | + | 36 |
| 225 | + | 30 | x | = | 9 | x | + | 36 |
| 30 | x | − | 9 | x | = | 36 | − | 225 |
| 21 | x | = | 36 | − | 225 |
| 21 | x | = | - | 189 |
| x | = | - | 189 | ÷ | 21 |
| = | - | 189 | × | 1 21 |
| = | - | 9 | × | 1 |
| x | = | - | 9 |