| 300 | ( | x | + | 1 | ) | ( | x | + | 1 | ) | = | 432 |
| Left side of the equation = | 300 | x | ( | x | + | 1 | ) | + | 300 | × | 1 | ( | x | + | 1 | ) |
| = | 300 | x | ( | x | + | 1 | ) | + | 300 | ( | x | + | 1 | ) |
| = | 300 | x | x | + | 300 | x | × | 1 | + | 300 | ( | x | + | 1 | ) |
| = | 300 | x | x | + | 300 | x | + | 300 | ( | x | + | 1 | ) |
| = | 300 | x | x | + | 300 | x | + | 300 | x | + | 300 | × | 1 |
| = | 300 | x | x | + | 300 | x | + | 300 | x | + | 300 |
| = | 300 | x | x | + | 600 | x | + | 300 |
| 300 | x | x | + | 600 | x | + | 300 | = | 432 |
| x1= | - | 11 5 |
| x2= | 1 5 |