| ( | 4 | n | + | 2 | ) | ( | 5 | n | − | 2 | ) | = | 62 |
| Left side of the equation = | 4 | n | ( | 5 | n | − | 2 | ) | + | 2 | ( | 5 | n | − | 2 | ) |
| = | 4 | n | × | 5 | n | − | 4 | n | × | 2 | + | 2 | ( | 5 | n | − | 2 | ) |
| = | 20 | n | n | − | 8 | n | + | 2 | ( | 5 | n | − | 2 | ) |
| = | 20 | n | n | − | 8 | n | + | 2 | × | 5 | n | − | 2 | × | 2 |
| = | 20 | n | n | − | 8 | n | + | 10 | n | − | 4 |
| = | 20 | n | n | + | 2 | n | − | 4 |
| 20 | n | n | + | 2 | n | − | 4 | = | 62 |