Question

A polygon has 44 diagonals, then the number of its sides are

• A. 11
• B. 7
• C. 8
• D. None of these

Answer 1

Answer: (C)

8

Answer 2

We have

44 = $nC_{2} - n = \frac{1}{2}n(n - 1) - n$

or $n^{2} - 3n - 88 = 0$ or $(n - 1!)(n + 8) = 0$

∴ n = 11, since n ≠ –8