| ( | 6 | ÷ | 31 | ) | × | 11 400 | + | ( | 25 | ÷ | 31 | ) | ( | 11 400 | a | + | 5 200 | ( | 1 | − | a | ) | ) | = | 0 |
| 方程左边 = | 6 | ÷ | 31 | × | 11 400 | + | ( | 25 | ÷ | 31 | ) | ( | 11 400 | a | + | 5 200 | ( | 1 | − | a | ) | ) |
| = | 33 6200 | + | ( | 25 | ÷ | 31 | ) | ( | 11 400 | a | + | 5 200 | ( | 1 | − | a | ) | ) |
| = | 33 6200 | + | 25 | ÷ | 31 | × | ( | 11 400 | a | + | 5 200 | ( | 1 | − | a | ) | ) |
| = | 33 6200 | + | 25 31 | ( | 11 400 | a | + | 5 200 | ( | 1 | − | a | ) | ) |
| = | 33 6200 | + | 25 31 | × | 11 400 | a | + | 25 31 | × | 5 200 | ( | 1 | − | a | ) |
| = | 33 6200 | + | 11 496 | a | + | 5 248 | ( | 1 | − | a | ) |
| = | 33 6200 | + | 11 496 | a | + | 5 248 | × | 1 | − | 5 248 | a |
| = | 33 6200 | + | 11 496 | a | + | 5 248 | − | 5 248 | a |
| = | 79 3100 | + | 1 496 | a |
79 3100 | + | 1 496 | a | = | 0 |
1 496 | a | = | 0 | − | 79 3100 |
1 496 | a | = | - | 79 3100 |
| a | = | - | 79 3100 | ÷ | 1 496 |
| = | - | 79 3100 | × | 496 |
| = | - | 79 775 | × | 124 |
| a | = | - | 9796 775 |
| a | = | - | 316 25 |
| a | = | - 12.64 |