( | x | − | 10 | ) | ( | 240 | − | 8 | x | ) | − | 168 | = | 600 |
方程左边 = | x | ( | 240 | − | 8 | x | ) | − | 10 | ( | 240 | − | 8 | x | ) | − | 168 |
= | x | × | 240 | − | x | × | 8 | x | − | 10 | ( | 240 | − | 8 | x | ) | − | 168 |
= | 240 | x | − | x | × | 8 | x | − | 10 | × | 240 | + | 10 | × | 8 | x | − | 168 |
= | 240 | x | − | x | × | 8 | x | − | 2400 | + | 80 | x | − | 168 |
= | 320 | x | − | x | × | 8 | x | − | 2568 |
320 | x | − | x | × | 8 | x | − | 2568 | = | 600 |