| ( | b | + | 2 | ) | ( | b | + | 2 | ) | − | 4 | ( | 6 | − | b | ) | = | 0 |
| Left side of the equation = | b | ( | b | + | 2 | ) | + | 2 | ( | b | + | 2 | ) | − | 4 | ( | 6 | − | b | ) |
| = | b | b | + | b | × | 2 | + | 2 | ( | b | + | 2 | ) | − | 4 | ( | 6 | − | b | ) |
| = | b | b | + | 2 | b | + | 2 | b | + | 2 | × | 2 | − | 4 | ( | 6 | − | b | ) |
| = | b | b | + | 2 | b | + | 2 | b | + | 4 | − | 4 | ( | 6 | − | b | ) |
| = | b | b | + | 4 | b | + | 4 | − | 4 | ( | 6 | − | b | ) |
| = | b | b | + | 4 | b | + | 4 | − | 4 | × | 6 | + | 4 | b |
| = | b | b | + | 4 | b | + | 4 | − | 24 | + | 4 | b |
| = | b | b | + | 8 | b | − | 20 |
| b | b | + | 8 | b | − | 20 | = | 0 |