| ( | b | − | 4 | ) | ( | b | − | 4 | ) | − | 4 | ( | - | b | + | 14 | ) | = | 0 |
| Left side of the equation = | b | ( | b | − | 4 | ) | − | 4 | ( | b | − | 4 | ) | − | 4 | ( | - | b | + | 14 | ) |
| = | b | b | − | b | × | 4 | − | 4 | ( | b | − | 4 | ) | − | 4 | ( | - | b | + | 14 | ) |
| = | b | b | − | 4 | b | − | 4 | b | + | 4 | × | 4 | − | 4 | ( | - | b | + | 14 | ) |
| = | b | b | − | 4 | b | − | 4 | b | + | 16 | − | 4 | ( | - | b | + | 14 | ) |
| = | b | b | − | 8 | b | + | 16 | − | 4 | ( | - | b | + | 14 | ) |
| = | b | b | − | 8 | b | + | 16 | + | 4 | b | − | 4 | × | 14 |
| = | b | b | − | 8 | b | + | 16 | + | 4 | b | − | 56 |
| = | b | b | − | 4 | b | − | 40 |
| b | b | − | 4 | b | − | 40 | = | 0 |