| 104 | a | − | 50 | ( | 1 | + | 2 | a | ) | ( | 1 | + | a | ) | − | 10 | = | 0 |
| Left side of the equation = | 104 | a | − | 50 | × | 1 | ( | 1 | + | a | ) | − | 50 | × | 2 | a | ( | 1 | + | a | ) | − | 10 |
| = | 104 | a | − | 50 | ( | 1 | + | a | ) | − | 100 | a | ( | 1 | + | a | ) | − | 10 |
| = | 104 | a | − | 50 | × | 1 | − | 50 | a | − | 100 | a | ( | 1 | + | a | ) | − | 10 |
| = | 104 | a | − | 50 | − | 50 | a | − | 100 | a | ( | 1 | + | a | ) | − | 10 |
| = | 54 | a | − | 60 | − | 100 | a | ( | 1 | + | a | ) |
| = | 54 | a | − | 60 | − | 100 | a | × | 1 | − | 100 | a | a |
| = | 54 | a | − | 60 | − | 100 | a | − | 100 | a | a |
| = | - | 46 | a | − | 60 | − | 100 | a | a |
| - | 46 | a | − | 60 | − | 100 | a | a | = | 0 |