| ( | 36 | + | x | ) | × | 9 | = | ( | 36 | − | 3 2 | x | ) | × | 4 |
| Left side of the equation = | 36 | × | 9 | + | x | × | 9 |
| = | 324 | + | x | × | 9 |
| 324 | + | 9 | x | = | ( | 36 | − | 3 2 | x | ) | × | 4 |
| Right side of the equation = | 36 | × | 4 | − | 3 2 | x | × | 4 |
| = | 144 | − | 6 | x |
| 324 | + | 9 | x | = | 144 | − | 6 | x |
| 9 | x | + | 6 | x | = | 144 | − | 324 |
| 15 | x | = | 144 | − | 324 |
| 15 | x | = | - | 180 |
| x | = | - | 180 | ÷ | 15 |
| = | - | 180 | × | 1 15 |
| = | - | 12 | × | 1 |
| x | = | - | 12 |