| ( | x | + | 1 | ) | ( | x | − | 2 | ) | ( | x | − | 5 | ) | = | 0 |
| Left side of the equation = | x | ( | x | − | 2 | ) | ( | x | − | 5 | ) | + | 1 | ( | x | − | 2 | ) | ( | x | − | 5 | ) |
| = | x | x | ( | x | − | 5 | ) | − | x | × | 2 | ( | x | − | 5 | ) | + | 1 | ( | x | − | 2 | ) | ( | x | − | 5 | ) |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | ( | x | − | 5 | ) | + | 1 | ( | x | − | 2 | ) | ( | x | − | 5 | ) |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | x | × | 2 | × | 5 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | x | × | 10 | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 10 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 10 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 10 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 10 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 5 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 5 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 5 | x | + | 1 |
| = | x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 3 | x | + | 1 |
| x | x | x | − | x | x | × | 5 | − | x | × | 2 | x | + | 3 | x | + | 1 | = | 0 |