| a | ( | 5 | a | + | 48 | ) | = | ( | a | + | 6 | ) | ( | 5 | a | + | 12 | ) |
| Left side of the equation = | a | × | 5 | a | + | a | × | 48 |
| a | × | 5 | a | + | 48 | a | = | ( | a | + | 6 | ) | ( | 5 | a | + | 12 | ) |
| Right side of the equation = | a | ( | 5 | a | + | 12 | ) | + | 6 | ( | 5 | a | + | 12 | ) |
| = | a | × | 5 | a | + | a | × | 12 | + | 6 | ( | 5 | a | + | 12 | ) |
| = | a | × | 5 | a | + | 12 | a | + | 6 | × | 5 | a | + | 6 | × | 12 |
| = | a | × | 5 | a | + | 12 | a | + | 30 | a | + | 72 |
| = | a | × | 5 | a | + | 42 | a | + | 72 |
| a | × | 5 | a | + | 48 | a | = | a | × | 5 | a | + | 42 | a | + | 72 |