| ( | 40000 | − | 2400 | × | 2 | ) | ÷ | ( | 210 | + | x | ) | = | 142 |
| Multiply both sides of the equation by: | ( | 210 | + | x | ) |
| ( | 40000 | − | 2400 | × | 2 | ) | = | 142 | ( | 210 | + | x | ) |
| 40000 | − | 2400 | × | 2 | = | 142 | ( | 210 | + | x | ) |
| 40000 | − | 2400 | × | 2 | = | 142 | × | 210 | + | 142 | x |
| 40000 | − | 4800 | = | 29820 | + | 142 | x |
| 35200 | = | 29820 | + | 142 | x |
| - | 142 | x | = | 29820 | − | 35200 |
| - | 142 | x | = | - | 5380 |
| 5380 | = | 142 | x |
| 142 | x | = | 5380 |
| x | = | 5380 | ÷ | 142 |
| = | 5380 | × | 1 142 |
| = | 2690 | × | 1 71 |
| x | = | 2690 71 |
| x | = | 37.887324 |