polygon

A polygon has 44 diagonals. The number of its sides is
(A) 10 (B) 11 (C) 12 (D) 13

1 Answers

n(n - 3)2 = 44 where n is no. of sides
â†’ n² - 3n - 88 = 0
â†’ (n - 11)(n+8) = 0
â†’ n = 11 or - 8
so n = 11 as n = -8 is absurd and not possible

so (b)

Note : no. of diagonals of a n sided polygon is given by n(n - 3)2 where n is number of sides

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