| 20 | × | 5 | + | ( | 19570 | − | x | ) | × | 5 | = | - | 100 |
| Left side of the equation = | 100 | + | ( | 19570 | − | x | ) | × | 5 |
| 100 | + | ( | 19570 | − | x | ) | × | 5 | = | - | 100 |
| Left side of the equation = | 100 | + | 19570 | × | 5 | − | x | × | 5 |
| = | 100 | + | 97850 | − | x | × | 5 |
| = | 97950 | − | 5 | x |
| 97950 | − | 5 | x | = | - | 100 |
| - | 5 | x | = | - | 100 | − | 97950 |
| - | 5 | x | = | - | 98050 |
| 98050 | = | 5 | x |
| 5 | x | = | 98050 |
| x | = | 98050 | ÷ | 5 |
| = | 98050 | × | 1 5 |
| = | 19610 | × | 1 |
| x | = | 19610 |