Question 213860
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ =\ 10 - 10x - x^2]


Put it into standard form, i.e. *[tex \LARGE y\ =\ ax^2 + bx + c]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ =\  - x^2 - 10x + 10]


Now you can see that *[tex \Large a\ =\ -1], *[tex \Large b\ =\ -10], and *[tex \Large c\ =\ 10].


Now your problem is a simple matter of substituting the values for *[tex \Large a] and *[tex \Large b] into:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ -\frac{b}{2a}]


and then doing the indicated arithmetic. 


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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