Question 222148
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There are


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{n(n-3)}{2}]


diagonals in a *[tex \Large n]-sided polygon.  Set the formula equal to 90 and solve for *[tex \Large n].


Hint: You will end up with a factorable quadratic.  You will get two roots.  Exclude the negative root because you cannot have a negative number of sides.



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