| 30 | X | X | × | 4 5 | = | ( | X | − | 5 | ) | X | × | 30 | X | × | 9 10 |
| Left side of the equation = | 24 | X | X |
| 24 | X | X | = | ( | X | − | 5 | ) | X | × | 30 | X | × | 9 10 |
| Right side of the equation = | ( | X | − | 5 | ) | X | × | 27 | X |
| 24 | X | X | = | ( | X | − | 5 | ) | X | × | 27 | X |
| Right side of the equation = | X | X | × | 27 | X | − | 5 | X | × | 27 | X |
| = | X | X | × | 27 | X | − | 135 | X | X |
| 24 | X | X | = | X | X | × | 27 | X | − | 135 | X | X |
| X3= | 53 9 |