(Q). A polygon has 65 diagonals then find its number of sides.
Solution:-
Let number of sides = n
∴ number of vertices = n
⟹ ⁿC₃ – n = 65
⟹ = 65
⟹ n(n-3) = 2×5×13
n(n-3) = 13(13 – 3)
∴ n = 13 Answer
(Q). A polygon has 65 diagonals then find its number of sides.
Solution:-
Let number of sides = n
∴ number of vertices = n
⟹ ⁿC₃ – n = 65
⟹ = 65
⟹ n(n-3) = 2×5×13
n(n-3) = 13(13 – 3)
∴ n = 13 Answer