| ( | x | + | 4 | ) | ( | x | + | 1 | ) | ( | x | − | 1 | ) | = | ( | x | − | 3 | ) |
| Left side of the equation = | x | ( | x | + | 1 | ) | ( | x | − | 1 | ) | + | 4 | ( | x | + | 1 | ) | ( | x | − | 1 | ) |
| = | x | x | ( | x | − | 1 | ) | + | x | × | 1 | ( | x | − | 1 | ) | + | 4 | ( | x | + | 1 | ) | ( | x | − | 1 | ) |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | ( | x | − | 1 | ) | + | 4 | ( | x | + | 1 | ) | ( | x | − | 1 | ) |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | x | × | 1 | × | 1 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | x | × | 1 | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 5 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 5 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 5 | x | + | 4 |
| = | x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 |
| x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 | = | ( | x | − | 3 | ) |
| Right side of the equation = | x | − | 3 |
| x | x | x | − | x | x | × | 1 | + | x | × | 1 | x | − | 1 | x | + | 4 | = | x | − | 3 |