### Home > GC > Chapter 9 > Lesson 9.1.2 > Problem9-21

9-21.

Review what you know about the angles of polygons below.

1. If the exterior angle of a polygon is $29°$, what is the interior angle?

What is the relationship between the interior and exterior angles of a polygon?

2. If the interior angle of a polygon is $170°$, can it be a regular polygon? Why or why not?

Refer to the Math Notes box in Lesson 8.1.4.

3. Find the sum of the interior angles of a regular $29$-gon.

To calculate the sum of the interior angles of a polygon use $(n − 2)180°$.
$\text{Sum of the interior angles in a 29-gon}=27\cdot180°=4860°$.