| ( | C | × | 2 | ) | × | 2 5 | ( | 1 | − | 2 5 | ) | × | 1 5 | = | 0 |
| Left side of the equation = | ( | C | × | 2 | ) | × | 2 25 | ( | 1 | − | 2 5 | ) |
| ( | C | × | 2 | ) | × | 2 25 | ( | 1 | − | 2 5 | ) | = | 0 |
| Left side of the equation = | C | × | 2 | × | 2 25 | ( | 1 | − | 2 5 | ) |
| = | C | × | 4 25 | ( | 1 | − | 2 5 | ) |
| = | C | × | 4 25 | × | 1 | − | C | × | 4 25 | × | 2 5 |
| = | C | × | 4 25 | − | C | × | 8 125 |
| = | 12 125 | C |
12 125 | C | = | 0 |
| C | = | 0 | ÷ | 12 125 |
| = | 0 | × | 125 12 |
| C | = | 0 |