| 4 | x | − | 5 | × | 5 | x | − | 10 | = | 9 | ÷ | 10 |
| Left side of the equation = | 4 | x | − | 25 | x | − | 10 |
| = | - | 21 | x | − | 10 |
| - | 21 | x | − | 10 | = | 9 | ÷ | 10 |
| Right side of the equation = | 9 10 |
| - | 21 | x | − | 10 | = | 9 10 |
| - | 21 | x | = | 9 10 | + | 10 |
| - | 21 | x | = | 109 10 |
| - | 109 10 | = | 21 | x |
| 21 | x | = | - | 109 10 |
| x | = | - | 109 10 | ÷ | 21 |
| = | - | 109 10 | × | 1 21 |
| x | = | - | 109 210 |
| x | = | - 0.519048 |