| 4500 | + | 21 200 | × | 6520 | + | 7 100 | a | − | a | = | 0 |
| Left side of the equation = | 4500 | + | 3423 5 | + | 7 100 | a | − | a |
| = | 25923 5 | − | 93 100 | a |
25923 5 | − | 93 100 | a | = | 0 |
| - | 93 100 | a | = | 0 | − | 25923 5 |
| - | 93 100 | a | = | - | 25923 5 |
25923 5 | = | 93 100 | a |
93 100 | a | = | 25923 5 |
| a | = | 25923 5 | ÷ | 93 100 |
| = | 25923 5 | × | 100 93 |
| = | 8641 | × | 20 31 |
| a | = | 172820 31 |
| a | = | 5574.83871 |