( | 90 | X | + | ( | 60 | − | X | ) | × | 75 | ) | ÷ | 60 | = | 0 |
方程左边 = | 90 | X | × | 1 60 | + | ( | 60 | − | X | ) | × | 75 | × | 1 60 |
= | 3 2 | X | + | ( | 60 | − | X | ) | × | 5 4 |
= | 3 2 | X | + | 60 | × | 5 4 | − | X | × | 5 4 |
= | 3 2 | X | + | 75 | − | X | × | 5 4 |
= | 1 4 | X | + | 75 |
1 4 | X | + | 75 | = | 0 |
1 4 | X | = | 0 | − | 75 |
1 4 | X | = | - | 75 |
X | = | - | 75 | ÷ | 1 4 |
= | - | 75 | × | 4 |
X | = | - | 300 |