( | 500 | + | 20 | ( | 58 | − | a | ) | ) | ( | a | − | 35 | ) | = | 8400 |
方程左边 = | 500 | ( | a | − | 35 | ) | + | 20 | ( | 58 | − | a | ) | ( | a | − | 35 | ) |
= | 500 | a | − | 500 | × | 35 | + | 20 | ( | 58 | − | a | ) | ( | a | − | 35 | ) |
= | 500 | a | − | 17500 | + | 20 | ( | 58 | − | a | ) | ( | a | − | 35 | ) |
= | 500 | a | − | 17500 | + | 20 | × | 58 | ( | a | − | 35 | ) | − | 20 | a | ( | a | − | 35 | ) |
= | 500 | a | − | 17500 | + | 1160 | ( | a | − | 35 | ) | − | 20 | a | ( | a | − | 35 | ) |
= | 500 | a | − | 17500 | + | 1160 | a | − | 1160 | × | 35 | − | 20 | a | ( | a | − | 35 | ) |
= | 500 | a | − | 17500 | + | 1160 | a | − | 40600 | − | 20 | a | ( | a | − | 35 | ) |
= | 1660 | a | − | 58100 | − | 20 | a | ( | a | − | 35 | ) |
= | 1660 | a | − | 58100 | − | 20 | a | a | + | 20 | a | × | 35 |
= | 1660 | a | − | 58100 | − | 20 | a | a | + | 700 | a |
= | 2360 | a | − | 58100 | − | 20 | a | a |
2360 | a | − | 58100 | − | 20 | a | a | = | 8400 |