X | ( | 1 | + | 50 100 | ) | × | 4 5 | ( | 1 | − | 5 100 | ) | = | X | + | 7 |
方程左边 = | X | × | 1 | × | 4 5 | ( | 1 | − | 5 100 | ) | + | X | × | 50 100 | × | 4 5 | ( | 1 | − | 5 100 | ) |
= | X | × | 4 5 | ( | 1 | − | 5 100 | ) | + | X | × | 2 5 | ( | 1 | − | 5 100 | ) |
= | X | × | 4 5 | × | 1 | − | X | × | 4 5 | × | 5 100 | + | X | × | 2 5 | ( | 1 | − | 5 100 | ) |
= | X | × | 4 5 | − | X | × | 1 25 | + | X | × | 2 5 | ( | 1 | − | 5 100 | ) |
= | 19 25 | X | + | X | × | 2 5 | ( | 1 | − | 5 100 | ) |
= | 19 25 | X | + | X | × | 2 5 | × | 1 | − | X | × | 2 5 | × | 5 100 |
= | 19 25 | X | + | X | × | 2 5 | − | X | × | 1 50 |
= | 57 50 | X |
57 50 | X | = | X | + | 7 |
57 50 | X | − | X | = | 7 |
7 50 | X | = | 7 |
X | = | 7 | ÷ | 7 50 |
= | 7 | × | 50 7 |
= | 1 | × | 50 |
X | = | 50 |