( | 11 | + | X | ) | ÷ | ( | 17 | + | X | ) | = | 3 | ÷ | 4 |
方程两边同时乘以: | ( | 17 | + | X | ) |
( | 11 | + | X | ) | = | 3 | ÷ | 4 | × | ( | 17 | + | X | ) |
11 | + | X | = | 3 | ÷ | 4 | × | ( | 17 | + | X | ) |
11 | + | X | = | 3 | ÷ | 4 | × | 17 | + | 3 | ÷ | 4 | × | X |
11 | + | X | = | 51 4 | + | 3 4 | X |
X | − | 3 4 | X | = | 51 4 | − | 11 |
1 4 | X | = | 51 4 | − | 11 |
1 4 | X | = | 7 4 |
X | = | 7 4 | ÷ | 1 4 |
= | 7 4 | × | 4 |
= | 7 | × | 1 |
X | = | 7 |