| 5 | ( | 1 | + | X | ) | + | 4 | × | 1 | + | 1 | × | 1 | = | 5 | ( | X | + | 3 | ) |
| Left side of the equation = | 5 | ( | 1 | + | X | ) | + | 4 | + | 1 |
| = | 5 | ( | 1 | + | X | ) | + | 5 |
| 5 | ( | 1 | + | X | ) | + | 5 | = | 5 | ( | X | + | 3 | ) |
| Left side of the equation = | 5 | × | 1 | + | 5 | X | + | 5 |
| = | 5 | + | 5 | X | + | 5 |
| = | 10 | + | 5 | X |
| 10 | + | 5 | X | = | 5 | ( | X | + | 3 | ) |
| Right side of the equation = | 5 | X | + | 5 | × | 3 |
| = | 5 | X | + | 15 |
| 10 | + | 5 | X | = | 5 | X | + | 15 |
| 5 | X | − | 5 | X | = | 15 | − | 10 |
| 0 | X | = | 15 | − | 10 |
| 0 | X | = | 5 |