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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
[ 1/1 Equation]
Work: Find the solution of equation a×30+120 = a×35+20 .
Question type: Equation
Solution:Original question:
| a | × | 30 | + | 120 | = | a | × | 35 | + | 20 |
Transposition :
| 30 | a | − | 35 | a | = | 20 | − | 120 |
Combine the items on the left of the equation:
| - | 5 | a | = | 20 | − | 120 |
Combine the items on the right of the equation:
| - | 5 | a | = | - | 100 |
By shifting the terms and changing the symbols on toth sides of the equation, we obtain :
| 100 | = | 5 | a |
If the left side of the equation is equal to the right side, then the right side must also be equal to the left side, that is :
| 5 | a | = | 100 |
The coefficient of the unknown number is reduced to 1 :
| a | = | 100 | ÷ | 5 |
| = | 100 | × | 1 5 |
| = | 20 | × | 1 |
We obtained :
| a | = | 20 |