( | 600 | − | ( | 2 | − | 40 | ) | × | 10 | ) | ( | x | − | 30 | ) | = | 10000 |
方程左边 = | 600 | ( | x | − | 30 | ) | − | ( | 2 | − | 40 | ) | × | 10 | ( | x | − | 30 | ) |
= | 600 | x | − | 600 | × | 30 | − | ( | 2 | − | 40 | ) | × | 10 | ( | x | − | 30 | ) |
= | 600 | x | − | 18000 | − | ( | 2 | − | 40 | ) | × | 10 | ( | x | − | 30 | ) |
= | 600 | x | − | 18000 | − | 2 | × | 10 | ( | x | − | 30 | ) | + | 40 | × | 10 | ( | x | − | 30 | ) |
= | 600 | x | − | 18000 | − | 20 | ( | x | − | 30 | ) | + | 400 | ( | x | − | 30 | ) |
= | 600 | x | − | 18000 | − | 20 | x | + | 20 | × | 30 | + | 400 | ( | x | − | 30 | ) |
= | 600 | x | − | 18000 | − | 20 | x | + | 600 | + | 400 | ( | x | − | 30 | ) |
= | 580 | x | − | 17400 | + | 400 | ( | x | − | 30 | ) |
= | 580 | x | − | 17400 | + | 400 | x | − | 400 | × | 30 |
= | 580 | x | − | 17400 | + | 400 | x | − | 12000 |
= | 980 | x | − | 29400 |
980 | x | − | 29400 | = | 10000 |
980 | x | = | 10000 | + | 29400 |
980 | x | = | 39400 |
x | = | 39400 | ÷ | 980 |
= | 39400 | × | 1 980 |
= | 1970 | × | 1 49 |
x | = | 1970 49 |
x | = | 40.204082 |