| ( | x | − | 2 | ) | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) | = | 0 |
| Left side of the equation = | x | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) | − | 2 | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) |
| = | x | × | 160 | − | x | × | 40 | ( | x | − | 38 | ) | − | 2 | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) |
| = | 160 | x | − | x | × | 40 | x | + | x | × | 40 | × | 38 | − | 2 | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) |
| = | 160 | x | − | x | × | 40 | x | + | x | × | 1520 | − | 2 | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) |
| = | 1680 | x | − | x | × | 40 | x | − | 2 | ( | 160 | − | 40 | ( | x | − | 38 | ) | ) |
| = | 1680 | x | − | x | × | 40 | x | − | 2 | × | 160 | + | 2 | × | 40 | ( | x | − | 38 | ) |
| = | 1680 | x | − | x | × | 40 | x | − | 320 | + | 80 | ( | x | − | 38 | ) |
| = | 1680 | x | − | x | × | 40 | x | − | 320 | + | 80 | x | − | 80 | × | 38 |
| = | 1680 | x | − | x | × | 40 | x | − | 320 | + | 80 | x | − | 3040 |
| = | 1760 | x | − | x | × | 40 | x | − | 3360 |
| 1760 | x | − | x | × | 40 | x | − | 3360 | = | 0 |