| a | + | ( | 286 | − | a | ) | ÷ | 10 | = | 2 | a |
| Left side of the equation = | a | + | 286 | × | 1 10 | − | a | × | 1 10 |
| = | a | + | 143 5 | − | a | × | 1 10 |
| = | 9 10 | a | + | 143 5 |
9 10 | a | + | 143 5 | = | 2 | a |
9 10 | a | − | 2 | a | = | - | 143 5 |
| - | 11 10 | a | = | - | 143 5 |
143 5 | = | 11 10 | a |
11 10 | a | = | 143 5 |
| a | = | 143 5 | ÷ | 11 10 |
| = | 143 5 | × | 10 11 |
| = | 13 | × | 2 |
| a | = | 26 |