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.
Answers:
1. If we choose one of the vertices, we can draw <u>n-3</u> diagonals.
2. These diagonals form <u>n-2</u> triangles.
3. The sum of the interior angle measures of a triangle is <u>180</u> degrees.
4. <u>n – 2</u> triangles would have an interior angle measure sum of <u>180</u> degrees.
5. Therefore, the sum of the measures of the interior angles of an n-gon is 180(n – 2)°.