| 30 | x | × | 15 | + | 180 | × | 30 | × | 120 | − | 30 | x | × | 315 2 | − | 315 2 | × | 180 | × | 30 | = | 0 |
| Left side of the equation = | 450 | x | + | 648000 | − | 4725 | x | − | 850500 |
| = | - | 4275 | x | − | 202500 |
| - | 4275 | x | − | 202500 | = | 0 |
| - | 4275 | x | = | 0 | + | 202500 |
| - | 4275 | x | = | 202500 |
| - | 202500 | = | 4275 | x |
| 4275 | x | = | - | 202500 |
| x | = | - | 202500 | ÷ | 4275 |
| = | - | 202500 | × | 1 4275 |
| = | - | 900 | × | 1 19 |
| x | = | - | 900 19 |
| x | = | - 47.368421 |