| ( | 5 | − | x | ) | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 | ( | 4 | − | x | ) | = | 0 |
| Left side of the equation = | 5 | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 | ( | 4 | − | x | ) |
| = | 5 | × | 6 | ( | 4 | − | x | ) | − | 5 | x | ( | 4 | − | x | ) | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 |
| = | 30 | ( | 4 | − | x | ) | − | 5 | x | ( | 4 | − | x | ) | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 | ( | 4 | − | x | ) |
| = | 30 | × | 4 | − | 30 | x | − | 5 | x | ( | 4 | − | x | ) | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) |
| = | 120 | − | 30 | x | − | 5 | x | ( | 4 | − | x | ) | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 |
| = | 120 | − | 30 | x | − | 5 | x | × | 4 | + | 5 | x | x | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) |
| = | 120 | − | 30 | x | − | 20 | x | + | 5 | x | x | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 |
| = | 120 | − | 50 | x | + | 5 | x | x | − | x | ( | 6 | − | x | ) | ( | 4 | − | x | ) | − | 4 | ( | 6 | − | x | ) | − | 4 |
| = | 120 | − | 50 | x | + | 5 | x | x | − | x | × | 6 | ( | 4 | − | x | ) | + | x | x | ( | 4 | − | x | ) |
| = | 120 | − | 50 | x | + | 5 | x | x | − | x | × | 6 | × | 4 | + | x | × | 6 | x |
| = | 120 | − | 50 | x | + | 5 | x | x | − | x | × | 24 | + | x | × | 6 | x | + | x |
| = | 120 | − | 74 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | ( | 4 | − | x | ) |
| = | 120 | − | 74 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 120 | − | 74 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 120 | − | 74 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 96 | − | 70 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 96 | − | 70 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 96 | − | 70 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| = | 80 | − | 66 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 |
| 80 | − | 66 | x | + | 5 | x | x | + | x | × | 6 | x | + | x | x | × | 4 | = | 0 |