| x | × | 26 25 | + | ( | 290 | − | x | ) | × | 21 20 | = | 303 |
| Left side of the equation = | 26 25 | x | + | 290 | × | 21 20 | − | x | × | 21 20 |
| = | 26 25 | x | + | 609 2 | − | x | × | 21 20 |
| = | - | 1 100 | x | + | 609 2 |
| - | 1 100 | x | + | 609 2 | = | 303 |
| - | 1 100 | x | = | 303 | − | 609 2 |
| - | 1 100 | x | = | - | 3 2 |
3 2 | = | 1 100 | x |
1 100 | x | = | 3 2 |
| x | = | 3 2 | ÷ | 1 100 |
| = | 3 2 | × | 100 |
| = | 3 | × | 50 |
| x | = | 150 |