| ( | 50 | − | 2 | x | ) | ( | 38 | − | 2 | x | ) | = | 1260 |
| Left side of the equation = | 50 | ( | 38 | − | 2 | x | ) | − | 2 | x | ( | 38 | − | 2 | x | ) |
| = | 50 | × | 38 | − | 50 | × | 2 | x | − | 2 | x | ( | 38 | − | 2 | x | ) |
| = | 1900 | − | 100 | x | − | 2 | x | ( | 38 | − | 2 | x | ) |
| = | 1900 | − | 100 | x | − | 2 | x | × | 38 | + | 2 | x | × | 2 | x |
| = | 1900 | − | 100 | x | − | 76 | x | + | 4 | x | x |
| = | 1900 | − | 176 | x | + | 4 | x | x |
| 1900 | − | 176 | x | + | 4 | x | x | = | 1260 |