17 20 | X | = | 500 | ( | 1 | − | 3 25 | ) | + | 22 25 | ( | X | − | 500 | ) |
| Right side of the equation = | 500 | × | 1 | − | 500 | × | 3 25 | + | 22 25 | ( | X | − | 500 | ) |
| = | 500 | − | 60 | + | 22 25 | ( | X | − | 500 | ) |
| = | 440 | + | 22 25 | ( | X | − | 500 | ) |
| = | 440 | + | 22 25 | X | − | 22 25 | × | 500 |
| = | 440 | + | 22 25 | X | − | 440 |
| = | 0 | + | 22 25 | X |
17 20 | X | = | 22 25 | X |
17 20 | X | − | 22 25 | X | = | 0 |
| - | 3 100 | X | = | 0 |
| - | 0 | = | 3 100 | X |
3 100 | X | = | - | 0 |
| X | = | - | 0 | ÷ | 3 100 |
| = | - | 0 | × | 100 3 |
| X | = | 0 |