| ( | 800 | + | X | ) | ( | 50 | − | X | ÷ | 25 | ) | = | 42025 |
| Left side of the equation = | 800 | ( | 50 | − | X | ÷ | 25 | ) | + | X | ( | 50 | − | X | ÷ | 25 | ) |
| = | 800 | × | 50 | − | 800 | X | ÷ | 25 | + | X | ( | 50 | − | X | ÷ | 25 | ) |
| = | 40000 | − | 32 | X | + | X | ( | 50 | − | X | ÷ | 25 | ) |
| = | 40000 | − | 32 | X | + | X | × | 50 | − | X | X | ÷ | 25 |
| = | 40000 | + | 18 | X | − | X | X | × | 1 25 |
| 40000 | + | 18 | X | − | X | X | × | 1 25 | = | 42025 |
| X1= | 1575 7 |
| X2= | 1575 7 |