80 | ( | 23 | − | X | ) | + | 80 | X | ( | 1 | − | 5 100 | ) | + | 80 | X | ( | 1 | − | 15 100 | ) | = | 2400 |
方程左边 = | 80 | × | 23 | − | 80 | X | + | 80 | X | ( | 1 | − | 5 100 | ) | + | 80 | X | ( | 1 | − | 15 100 | ) |
= | 1840 | − | 80 | X | + | 80 | X | ( | 1 | − | 5 100 | ) | + | 80 | X | ( | 1 | − | 15 100 | ) |
= | 1840 | − | 80 | X | + | 80 | X | × | 1 | − | 80 | X | × | 5 100 | + | 80 | X | ( | 1 | − | 15 100 | ) |
= | 1840 | − | 80 | X | + | 80 | X | − | 4 | X | + | 80 | X | ( | 1 | − | 15 100 | ) |
= | 1840 | − | 4 | X | + | 80 | X | ( | 1 | − | 15 100 | ) |
= | 1840 | − | 4 | X | + | 80 | X | × | 1 | − | 80 | X | × | 15 100 |
= | 1840 | − | 4 | X | + | 80 | X | − | 12 | X |
= | 1840 | + | 64 | X |
1840 | + | 64 | X | = | 2400 |
64 | X | = | 2400 | − | 1840 |
64 | X | = | 560 |
X | = | 560 | ÷ | 64 |
= | 560 | × | 1 64 |
= | 35 | × | 1 4 |
X | = | 35 4 |
X | = | 8.75 |