Question

Splitting a polygon into triangles is a method used in calculating the sum of the interior angles of a polygon. Using this method, how many triangles does a 7-sided polygon contain?

A.
5.
B.
6.
C.
7.
D.
8.

Answer 1

Lets say that a quadrilateral has been divided into two triangles, so the interior angles add up to 2 × 180 = 360°. This pentagon has been divided into three triangles, so the interior angles add up to 3 × 180 = 540°. In the same way, a hexagon can be divided into 4 triangles, a 7-sided polygon into 5 triangles etc.
so your answer is A. 5
(^>^)