| x | ( | x | + | 1 | ) | ( | x | + | 1 | + | 1 | ) | = | 504 |
| Left side of the equation = | x | x | ( | x | + | 1 | + | 1 | ) | + | x | × | 1 | ( | x | + | 1 | + | 1 | ) |
| = | x | x | x | + | x | x | × | 1 | + | x | x | × | 1 | + | x | × | 1 | ( | x | + | 1 | + | 1 | ) |
| = | x | x | x | + | x | x | × | 1 | + | x | x | × | 1 | + | x | × | 1 | x |
| = | x | x | x | + | x | x | × | 1 | + | x | x | × | 1 | + | x | × | 1 | x |
| = | x | x | x | + | x | x | × | 1 | + | x | x | × | 1 | + | x | × | 1 | x |
| x | x | x | + | x | x | × | 1 | + | x | x | × | 1 | + | x | × | 1 | x | = | 504 |