| ( | - | 3 | − | x | ) | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) | = | 0 |
| Left side of the equation = | - | 3 | ( | 1 | − | x | ) | ( | 5 | − | x | ) | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 3 | × | 1 | ( | 5 | − | x | ) | + | 3 | x | ( | 5 | − | x | ) | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 3 | ( | 5 | − | x | ) | + | 3 | x | ( | 5 | − | x | ) | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 3 | × | 5 | + | 3 | x | + | 3 | x | ( | 5 | − | x | ) | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 15 | + | 3 | x | + | 3 | x | ( | 5 | − | x | ) | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 15 | + | 3 | x | + | 3 | x | × | 5 | − | 3 | x | x | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) |
| = | - | 15 | + | 3 | x | + | 15 | x | − | 3 | x | x | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 |
| = | - | 15 | + | 18 | x | − | 3 | x | x | − | x | ( | 1 | − | x | ) | ( | 5 | − | x | ) | + | 5 | ( | 3 | + | x | ) |
| = | - | 15 | + | 18 | x | − | 3 | x | x | − | x | × | 1 | ( | 5 | − | x | ) | + | x | x | ( | 5 | − | x | ) |
| = | - | 15 | + | 18 | x | − | 3 | x | x | − | x | × | 1 | × | 5 | + | x | × | 1 | x |
| = | - | 15 | + | 18 | x | − | 3 | x | x | − | x | × | 5 | + | x | × | 1 | x | + | x |
| = | - | 15 | + | 13 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | ( | 5 | − | x | ) |
| = | - | 15 | + | 13 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | × | 5 |
| = | - | 15 | + | 13 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | × | 5 |
| = | - | 15 | + | 13 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | × | 5 |
| = | - | 0 | + | 18 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | × | 5 |
| - | 0 | + | 18 | x | − | 3 | x | x | + | x | × | 1 | x | + | x | x | × | 5 | = | 0 |