| 64 | − | X | X | = | 36 | − | ( | 10 | − | X | ) | ( | 10 | − | X | ) |
| Right side of the equation = | 36 | − | 10 | ( | 10 | − | X | ) | + | X | ( | 10 | − | X | ) |
| = | 36 | − | 10 | × | 10 | + | 10 | X | + | X | ( | 10 | − | X | ) |
| = | 36 | − | 100 | + | 10 | X | + | X | ( | 10 | − | X | ) |
| = | - | 64 | + | 10 | X | + | X | ( | 10 | − | X | ) |
| = | - | 64 | + | 10 | X | + | X | × | 10 | − | X | X |
| = | - | 64 | + | 20 | X | − | X | X |
| 64 | − | X | X | = | - | 64 | + | 20 | X | − | X | X |
| X= | 32 5 |