| X | ( | 1 | − | 1 4 | ) | + | 63 | = | X | ( | 1 | + | 1 5 | ) |
| Left side of the equation = | X | × | 1 | − | X | × | 1 4 | + | 63 |
| = | 3 4 | X | + | 63 |
3 4 | X | + | 63 | = | X | ( | 1 | + | 1 5 | ) |
| Right side of the equation = | X | × | 1 | + | X | × | 1 5 |
| = | 6 5 | X |
3 4 | X | + | 63 | = | 6 5 | X |
3 4 | X | − | 6 5 | X | = | - | 63 |
| - | 9 20 | X | = | - | 63 |
| 63 | = | 9 20 | X |
9 20 | X | = | 63 |
| X | = | 63 | ÷ | 9 20 |
| = | 63 | × | 20 9 |
| = | 7 | × | 20 |
| X | = | 140 |