| ( | x | + | 2 | ) | ( | x | + | 7 | ) | = | ( | x | + | 3 | ) | ( | x | + | 6 | ) |
| Left side of the equation = | x | ( | x | + | 7 | ) | + | 2 | ( | x | + | 7 | ) |
| = | x | x | + | x | × | 7 | + | 2 | ( | x | + | 7 | ) |
| = | x | x | + | 7 | x | + | 2 | x | + | 2 | × | 7 |
| = | x | x | + | 7 | x | + | 2 | x | + | 14 |
| = | x | x | + | 9 | x | + | 14 |
| x | x | + | 9 | x | + | 14 | = | ( | x | + | 3 | ) | ( | x | + | 6 | ) |
| Right side of the equation = | x | ( | x | + | 6 | ) | + | 3 | ( | x | + | 6 | ) |
| = | x | x | + | x | × | 6 | + | 3 | ( | x | + | 6 | ) |
| = | x | x | + | 6 | x | + | 3 | x | + | 3 | × | 6 |
| = | x | x | + | 6 | x | + | 3 | x | + | 18 |
| = | x | x | + | 9 | x | + | 18 |
| x | x | + | 9 | x | + | 14 | = | x | x | + | 9 | x | + | 18 |