| ( | 38 | − | 5 | x | ) | ( | 2 | + | x | ) | = | 115 |
| Left side of the equation = | 38 | ( | 2 | + | x | ) | − | 5 | x | ( | 2 | + | x | ) |
| = | 38 | × | 2 | + | 38 | x | − | 5 | x | ( | 2 | + | x | ) |
| = | 76 | + | 38 | x | − | 5 | x | ( | 2 | + | x | ) |
| = | 76 | + | 38 | x | − | 5 | x | × | 2 | − | 5 | x | x |
| = | 76 | + | 38 | x | − | 10 | x | − | 5 | x | x |
| = | 76 | + | 28 | x | − | 5 | x | x |
| 76 | + | 28 | x | − | 5 | x | x | = | 115 |
| x1= | 13 5 |
| x2=3 |