| 60 | ( | x | − | 1 | ) | = | 40 | ( | x | + | 1 | ) |
| Left side of the equation = | 60 | x | − | 60 | × | 1 |
| = | 60 | x | − | 60 |
| 60 | x | − | 60 | = | 40 | ( | x | + | 1 | ) |
| Right side of the equation = | 40 | x | + | 40 | × | 1 |
| = | 40 | x | + | 40 |
| 60 | x | − | 60 | = | 40 | x | + | 40 |
| 60 | x | − | 40 | x | = | 40 | + | 60 |
| 20 | x | = | 40 | + | 60 |
| 20 | x | = | 100 |
| x | = | 100 | ÷ | 20 |
| = | 100 | × | 1 20 |
| = | 5 | × | 1 |
| x | = | 5 |