The sum of interior angles of a polygon is 2880^o. Find

      

The sum of interior angles of a polygon is 2880^o. Find
(a) The number of sides the polygon has.
(b) The number of triangles which can be formed when diagonals are drawn from one vertex connecting the other vertices.

  

Answers

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(a) (2n - 4)90 = 2880

180n - 360 = 2880

180n = 3240; n = 18 sides

(b) The number of triangles is

(n - 2) = 18 - 2 = 16

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johnmulu answered the question on June 9, 2017 at 13:20

Next: Two of the interior angles of a pentagon are 100^o and 140^o. Find the remaining angles if they are all equal.
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