30 | X | − | 30 | X | + | ( | 21 | + | 30 | X | ) | × | 1 10 | = | 26 |
方程左边 = | 0 | X | + | ( | 21 | + | 30 | X | ) | × | 1 10 |
0 | X | + | ( | 21 | + | 30 | X | ) | × | 1 10 | = | 26 |
方程左边 = | 0 | X | + | 21 | × | 1 10 | + | 30 | X | × | 1 10 |
= | 0 | X | + | 21 10 | + | 3 | X |
= | 3 | X | + | 21 10 |
3 | X | + | 21 10 | = | 26 |
3 | X | = | 26 | − | 21 10 |
3 | X | = | 239 10 |
X | = | 239 10 | ÷ | 3 |
= | 239 10 | × | 1 3 |
X | = | 239 30 |
X | = | 7.966667 |