6.1k views
1 vote
If the sum of the measures of the interior angles of a polygon is 1920°, how many sides does it have?

1 Answer

6 votes

Answer:

The regular polygon has 13 sides

Correct statement and question:

If the sum of the measures of the interior angles of a polygon is 1980°, how many sides does it have?

Source:

1,920° is not a valid value for a regular polygon. It should be either 1,980° or 1,800° (it has to be a multiple of 180). We pick 1,980° to answer the question.

Explanation:

Let's recall that the formula of the sum of the interior angles of any polygon is:

Sum of Interior Angles = (n-2) * 180°, where n is the number of sides of the polygon.

Therefore, replacing with the value we know:

1,980 = (n-2) * 180

n - 2 = 1,980/180

n - 2 = 11

n = 13

User Robotadam
by
3.7k points