why is it possible to find the sum of the angle meanures of an n-gon using the formula (180n-360)??

To understand why the formula (180n - 360) can be used to find the sum of the angle measures of an n-gon, let's break it down step by step.

1. Start with a triangle (n = 3). The sum of the angle measures of any triangle is always 180 degrees. This is a basic property of triangles.

2. Now, consider a quadrilateral (n = 4), which consists of two triangles. You can divide a quadrilateral into two triangles by drawing a diagonal. Since each triangle has an angle sum of 180 degrees, the quadrilateral has a sum of 2 * 180 = 360 degrees.

3. Continuing this pattern, a pentagon (n = 5) can be divided into three triangles by drawing non-intersecting diagonals. So, the sum of the angle measures of a pentagon is 3 * 180 = 540 degrees.

4. If we generalize this pattern, we can see that the sum of the angle measures of an n-gon can be given as (n - 2) * 180. However, this formula counts the total interior degrees of the n-gon.

5. To find the sum of the angle measures for the exterior angles, we can subtract this total from the sum of the exterior angles of a complete rotation, which is always 360 degrees.

So, the sum of the angle measures of an n-gon can be calculated as:

Sum of interior angles = (n - 2) * 180 degrees
Sum of exterior angles = Sum of interior angles of a complete rotation - Sum of interior angles
= 360 degrees - [(n - 2) * 180 degrees]

Simplifying this expression gives us the formula:

Sum of angle measures of an n-gon = 180n - 360

Therefore, it is possible to find the sum of the angle measures of an n-gon using the formula (180n - 360).