| 4 | x | − | 3 | ( | 20 | − | x | ) | = | 6 | x | − | 7 | ( | 9 | − | x | ) |
| Left side of the equation = | 4 | x | − | 3 | × | 20 | + | 3 | x |
| = | 4 | x | − | 60 | + | 3 | x |
| = | 7 | x | − | 60 |
| 7 | x | − | 60 | = | 6 | x | − | 7 | ( | 9 | − | x | ) |
| Right side of the equation = | 6 | x | − | 7 | × | 9 | + | 7 | x |
| = | 6 | x | − | 63 | + | 7 | x |
| = | 13 | x | − | 63 |
| 7 | x | − | 60 | = | 13 | x | − | 63 |
| 7 | x | − | 13 | x | = | - | 63 | + | 60 |
| - | 6 | x | = | - | 63 | + | 60 |
| - | 6 | x | = | - | 3 |
| 3 | = | 6 | x |
| 6 | x | = | 3 |
| x | = | 3 | ÷ | 6 |
| = | 3 | × | 1 6 |
| = | 1 | × | 1 2 |
| x | = | 1 2 |
| x | = | 0.5 |