( | 10 | − | 1 2 | x | ) | ( | 48 | + | 4 | x | ) | = | 510 |
方程左边 = | 10 | ( | 48 | + | 4 | x | ) | − | 1 2 | x | ( | 48 | + | 4 | x | ) |
= | 10 | × | 48 | + | 10 | × | 4 | x | − | 1 2 | x | ( | 48 | + | 4 | x | ) |
= | 480 | + | 40 | x | − | 1 2 | x | ( | 48 | + | 4 | x | ) |
= | 480 | + | 40 | x | − | 1 2 | x | × | 48 | − | 1 2 | x | × | 4 | x |
= | 480 | + | 40 | x | − | 24 | x | − | 2 | x | x |
= | 480 | + | 16 | x | − | 2 | x | x |
480 | + | 16 | x | − | 2 | x | x | = | 510 |