7 20 | x | + | ( | 4800 | − | x | ) | × | 3 500 | = | 124 5 |
| Left side of the equation = | 7 20 | x | + | 4800 | × | 3 500 | − | x | × | 3 500 |
| = | 7 20 | x | + | 144 5 | − | x | × | 3 500 |
| = | 43 125 | x | + | 144 5 |
43 125 | x | + | 144 5 | = | 124 5 |
43 125 | x | = | 124 5 | − | 144 5 |
43 125 | x | = | - | 4 |
| x | = | - | 4 | ÷ | 43 125 |
| = | - | 4 | × | 125 43 |
| x | = | - | 500 43 |
| x | = | - 11.627907 |