( | X | − | 20 | ) | X | ( | 50 | − | ( | X | − | 180 | ) | ÷ | 10 | ) | = | 0 |
方程左边 = | X | X | ( | 50 | − | ( | X | − | 180 | ) | ÷ | 10 | ) | − | 20 | X | ( | 50 | − | ( | X | − | 180 | ) | ÷ | 10 | ) |
= | X | X | × | 50 | − | X | X | ( | X | − | 180 | ) | ÷ | 10 | − | 20 | X | ( | 50 | − | ( | X | − | 180 | ) | ÷ | 10 | ) |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 180 | × | 1 10 | − | 20 |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 20 | X |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 20 | X |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 1000 | X |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 1000 | X |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 1000 | X |
= | X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 1360 | X |
X | X | × | 50 | − | X | X | X | × | 1 10 | + | X | X | × | 18 | − | 1360 | X | = | 0 |