| 4 | ( | x | − | 1 | ) | − | 3 | ( | 20 | − | x | ) | = | 5 | ( | x | − | 2 | ) |
| Left side of the equation = | 4 | x | − | 4 | × | 1 | − | 3 | ( | 20 | − | x | ) |
| = | 4 | x | − | 4 | − | 3 | ( | 20 | − | x | ) |
| = | 4 | x | − | 4 | − | 3 | × | 20 | + | 3 | x |
| = | 4 | x | − | 4 | − | 60 | + | 3 | x |
| = | 7 | x | − | 64 |
| 7 | x | − | 64 | = | 5 | ( | x | − | 2 | ) |
| Right side of the equation = | 5 | x | − | 5 | × | 2 |
| = | 5 | x | − | 10 |
| 7 | x | − | 64 | = | 5 | x | − | 10 |
| 7 | x | − | 5 | x | = | - | 10 | + | 64 |
| 2 | x | = | - | 10 | + | 64 |
| 2 | x | = | 54 |
| x | = | 54 | ÷ | 2 |
| = | 54 | × | 1 2 |
| = | 27 | × | 1 |
| x | = | 27 |