Question 327251
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Just use the quadratic formula.



*[tex \LARGE \ \ \ \ \ \ \ \ \ \ x\ =\ \frac{-b\ \pm\ \sqrt{b^2\ -\ 4ac}}{2a}]


where *[tex \LARGE a\ =\ 1], *[tex \LARGE b\ =\ 5], and *[tex \LARGE c\ =\ -7]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ x\ =\ \frac{-(5)\ \pm\ \sqrt{(5)^2\ -\ 4(1)(-7)}}{2(1)}]


Do the arithmetic and simplify for the exact answer, then punch your calculator buttons for the numeric approximation.  The discriminant is prime, so simplifying the expression is trivial.


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