| ( | 30 | − | 2 | X | ) | ( | 20 | − | X | ) | = | 532 |
| Left side of the equation = | 30 | ( | 20 | − | X | ) | − | 2 | X | ( | 20 | − | X | ) |
| = | 30 | × | 20 | − | 30 | X | − | 2 | X | ( | 20 | − | X | ) |
| = | 600 | − | 30 | X | − | 2 | X | ( | 20 | − | X | ) |
| = | 600 | − | 30 | X | − | 2 | X | × | 20 | + | 2 | X | X |
| = | 600 | − | 30 | X | − | 40 | X | + | 2 | X | X |
| = | 600 | − | 70 | X | + | 2 | X | X |
| 600 | − | 70 | X | + | 2 | X | X | = | 532 |