( | 40 | − | x | ) | × | 15 | = | ( | 60 | − | x | ) | × | 9 |
方程左边 = | 40 | × | 15 | − | x | × | 15 |
= | 600 | − | x | × | 15 |
600 | − | 15 | x | = | ( | 60 | − | x | ) | × | 9 |
方程右边 = | 60 | × | 9 | − | x | × | 9 |
= | 540 | − | x | × | 9 |
600 | − | 15 | x | = | 540 | − | 9 | x |
- | 15 | x | + | 9 | x | = | 540 | − | 600 |
- | 6 | x | = | 540 | − | 600 |
- | 6 | x | = | - | 60 |
60 | = | 6 | x |
6 | x | = | 60 |
x | = | 60 | ÷ | 6 |
= | 60 | × | 1 6 |
= | 10 | × | 1 |
x | = | 10 |