200 | ( | 1 | + | x | ) | ( | 1 | + | x | ) | = | 288 |
方程左边 = | 200 | × | 1 | ( | 1 | + | x | ) | + | 200 | x | ( | 1 | + | x | ) |
= | 200 | ( | 1 | + | x | ) | + | 200 | x | ( | 1 | + | x | ) |
= | 200 | × | 1 | + | 200 | x | + | 200 | x | ( | 1 | + | x | ) |
= | 200 | + | 200 | x | + | 200 | x | ( | 1 | + | x | ) |
= | 200 | + | 200 | x | + | 200 | x | × | 1 | + | 200 | x | x |
= | 200 | + | 200 | x | + | 200 | x | + | 200 | x | x |
= | 200 | + | 400 | x | + | 200 | x | x |
200 | + | 400 | x | + | 200 | x | x | = | 288 |
x1= | - | 11 5 |
x2= | 1 5 |