( | X | ÷ | 5 | ) | + | ( | 51 | − | X | ) | ÷ | 12 | = | ( | 51 | − | X | ) | ÷ | 4 | + | ( | X | ÷ | 12 | ) |
方程左边 = | X | ÷ | 5 | + | ( | 51 | − | X | ) | × | 1 12 |
= | 1 5 | X | + | 51 | × | 1 12 | − | X | × | 1 12 |
= | 1 5 | X | + | 17 4 | − | X | × | 1 12 |
= | 7 60 | X | + | 17 4 |
7 60 | X | + | 17 4 | = | ( | 51 | − | X | ) | ÷ | 4 | + | ( | X | ÷ | 12 | ) |
方程右边 = | 51 | × | 1 4 | − | X | × | 1 4 | + | ( | X | ÷ | 12 | ) |
= | 51 4 | − | X | × | 1 4 | + | ( | X | ÷ | 12 | ) |
= | 51 4 | − | 1 4 | X | + | X | ÷ | 12 |
= | 51 4 | − | 1 6 | X |
7 60 | X | + | 17 4 | = | 51 4 | − | 1 6 | X |
7 60 | X | + | 1 6 | X | = | 51 4 | − | 17 4 |
17 60 | X | = | 51 4 | − | 17 4 |
17 60 | X | = | 17 2 |
X | = | 17 2 | ÷ | 17 60 |
= | 17 2 | × | 60 17 |
= | 1 | × | 30 |
X | = | 30 |