| 4 | ( | 90 | − | 6 | x | ) | = | 13 2 | × | 4 | + | 22 |
| Left side of the equation = | 4 | × | 90 | − | 4 | × | 6 | x |
| = | 360 | − | 24 | x |
| 360 | − | 24 | x | = | 13 2 | × | 4 | + | 22 |
| Right side of the equation = | 26 | + | 22 |
| = | 48 |
| 360 | − | 24 | x | = | 48 |
| - | 24 | x | = | 48 | − | 360 |
| - | 24 | x | = | - | 312 |
| 312 | = | 24 | x |
| 24 | x | = | 312 |
| x | = | 312 | ÷ | 24 |
| = | 312 | × | 1 24 |
| = | 13 | × | 1 |
| x | = | 13 |