Given: an n-gon

Prove: The sum of the measures of the interior angles is 180(n – 2)°.

Complete the missing parts of the paragraph proof.

We are given an n-gon, which has n sides and n vertices. If we choose one of the vertices, we can draw diagonals. These diagonals form triangles. The sum of the interior angle measures of a triangle is degrees. n – 2 triangles would have an interior angle measure sum of . Therefore, the sum of the measures of the interior angles of an n-gon is 180(n – 2)°.