| 1 | + | 2 | ( | 1 | − | 3 | ( | - | 18 | + | 4 | x | ) | ) | = | - | 5 | ( | 7 | x | + | 13 | ) |
| Left side of the equation = | 1 | + | 2 | × | 1 | − | 2 | × | 3 | ( | - | 18 | + | 4 | x | ) |
| = | 1 | + | 2 | − | 6 | ( | - | 18 | + | 4 | x | ) |
| = | 3 | − | 6 | ( | - | 18 | + | 4 | x | ) |
| = | 3 | + | 6 | × | 18 | − | 6 | × | 4 | x |
| = | 3 | + | 108 | − | 24 | x |
| = | 111 | − | 24 | x |
| 111 | − | 24 | x | = | - | 5 | ( | 7 | x | + | 13 | ) |
| Right side of the equation = | - | 5 | × | 7 | x | − | 5 | × | 13 |
| = | - | 35 | x | − | 65 |
| 111 | − | 24 | x | = | - | 35 | x | − | 65 |
| - | 24 | x | + | 35 | x | = | - | 65 | − | 111 |
| 11 | x | = | - | 65 | − | 111 |
| 11 | x | = | - | 176 |
| x | = | - | 176 | ÷ | 11 |
| = | - | 176 | × | 1 11 |
| = | - | 16 | × | 1 |
| x | = | - | 16 |