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It supports mathematical functions (including trigonometric functions).
Current location：Mathematical operation > History of Mathematical Computation > Answer
Overview: 1 questions will be solved this time.Among them
☆1 equations
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Work: Find the solution of equation （80-y-65）（100＋10y） = 1560 .
Question type: Equation
Solution:Original question:
| ( | 80 | − | y | − | 65 | ) | ( | 100 | + | 10 | y | ) | = | 1560 |
| Left side of the equation = | 80 | ( | 100 | + | 10 | y | ) | − | y | ( | 100 | + | 10 | y | ) | − | 65 | ( | 100 | + | 10 | y | ) |
| = | 80 | × | 100 | + | 80 | × | 10 | y | − | y | ( | 100 | + | 10 | y | ) | − | 65 | ( | 100 | + | 10 | y | ) |
| = | 8000 | + | 800 | y | − | y | ( | 100 | + | 10 | y | ) | − | 65 | ( | 100 | + | 10 | y | ) |
| = | 8000 | + | 800 | y | − | y | × | 100 | − | y | × | 10 | y | − | 65 | ( | 100 | + | 10 | y | ) |
| = | 8000 | + | 700 | y | − | y | × | 10 | y | − | 65 | ( | 100 | + | 10 | y | ) |
| = | 8000 | + | 700 | y | − | y | × | 10 | y | − | 65 | × | 100 | − | 65 | × | 10 | y |
| = | 8000 | + | 700 | y | − | y | × | 10 | y | − | 6500 | − | 650 | y |
| = | 1500 | + | 50 | y | − | y | × | 10 | y |
| 1500 | + | 50 | y | − | y | × | 10 | y | = | 1560 |
After the equation is converted into a general formula, it is converted into:
( y - 2 )( y - 3 )=0
From
y - 2 = 0
y - 3 = 0
it is concluded that:：
y1=2
y2=3
There are 2 solution(s).
解一元二次方程的详细方法请参阅：《一元二次方程的解法》