17 200 | X | + | 18 100 | ( | 1 | − | X | ) | = | 71 500 |
方程左边 = | 17 200 | X | + | 18 100 | × | 1 | − | 18 100 | X |
= | 17 200 | X | + | 9 50 | − | 18 100 | X |
= | - | 19 200 | X | + | 9 50 |
- | 19 200 | X | + | 9 50 | = | 71 500 |
- | 19 200 | X | = | 71 500 | − | 9 50 |
- | 19 200 | X | = | - | 19 500 |
19 500 | = | 19 200 | X |
19 200 | X | = | 19 500 |
X | = | 19 500 | ÷ | 19 200 |
= | 19 500 | × | 200 19 |
= | 1 5 | × | 2 |
X | = | 2 5 |
X | = | 0.4 |