( | x | − | 8 | ) | ( | - | 5 | x | + | 150 | ) | = | 360 |
方程左边 = | x | ( | - | 5 | x | + | 150 | ) | − | 8 | ( | - | 5 | x | + | 150 | ) |
= | - | x | × | 5 | x | + | x | × | 150 | − | 8 | ( | - | 5 | x | + | 150 | ) |
= | - | x | × | 5 | x | + | 150 | x | + | 8 | × | 5 | x | − | 8 | × | 150 |
= | - | x | × | 5 | x | + | 150 | x | + | 40 | x | − | 1200 |
= | - | x | × | 5 | x | + | 190 | x | − | 1200 |
- | x | × | 5 | x | + | 190 | x | − | 1200 | = | 360 |