| 720 | − | 3 2 | x | × | 8 | = | 12 | ( | 180 | − | 7 | x | ) |
| Left side of the equation = | 720 | − | 12 | x |
| 720 | − | 12 | x | = | 12 | ( | 180 | − | 7 | x | ) |
| Right side of the equation = | 12 | × | 180 | − | 12 | × | 7 | x |
| = | 2160 | − | 84 | x |
| 720 | − | 12 | x | = | 2160 | − | 84 | x |
| - | 12 | x | + | 84 | x | = | 2160 | − | 720 |
| 72 | x | = | 2160 | − | 720 |
| 72 | x | = | 1440 |
| x | = | 1440 | ÷ | 72 |
| = | 1440 | × | 1 72 |
| = | 20 | × | 1 |
| x | = | 20 |