Question

Will give 25 points!!!! please help!!

Consider the marked interior angles in the regular pentagon and the concave pentagon in the following image, and then answer the questions below.


a. After looking at the sum of the angle measures of these polygons, what would you guess would be the sum of the interior angles of a
17-gon? Explain your reasoning.
b. What would you guess would be the sum of the interior angles of a
concave 17-gon? Explain your reasoning.
c. In your own words, explain why the sum of the exterior angles of any
convex polygon always equals 360°.
d. What would you guess would be the sum of the exterior angles of a
concave polygon? Explain your reasoning.

Answer 1

a. The sum of the angle measures of the regular pentagon is 540 degrees, and the sum of the angle measures of the concave pentagon is 720 degrees. Both of these polygons have five sides. If we assume that the sum of the angle measures of a polygon with n sides is proportional to n, we can use the ratios of the number of sides in each polygon to make an estimate for the sum of the interior angles of a 17-gon. The ratio of the number of sides in a 17-gon to the number of sides in a regular pentagon is 17/5. If we multiply the sum of the angle measures of the regular pentagon by this ratio, we get an estimate for the sum of the angle measures of a 17-gon:

540 * (17/5) = 1836 degrees.

So, we would guess that the sum of the interior angles of a 17-gon is 1836 degrees.

b. We can use a similar reasoning as in part (a) to estimate the sum of the interior angles of a concave 17-gon. The ratio of the number of sides in a concave pentagon to the number of sides in a concave 17-gon is 5/17. If we multiply the sum of the angle measures of the concave pentagon by this ratio, we get an estimate for the sum of the angle measures of a concave 17-gon:

720 * (5/17) = 211.76 degrees.

So, we would guess that the sum of the interior angles of a concave 17-gon is 211.76 degrees.

c. The sum of the exterior angles of a convex polygon always equals 360 degrees because the exterior angle at each vertex of the polygon is equal to the sum of the two adjacent interior angles. If we add up all of the exterior angles of a polygon, we are essentially adding up all of the vertex angles twice (once for each adjacent exterior angle). Therefore, the sum of the exterior angles of a convex polygon is equal to 2 times the sum of the interior angles. Since the sum of the interior angles of any n-sided polygon is (n-2)*180 degrees, the sum of the exterior angles is:

2 * (n-2) * 180 = 360(n-2) degrees.

d. It is not possible to make a generalization about the sum of the exterior angles of a concave polygon, because the sum of the exterior angles of a concave polygon can be greater than, less than, or equal to 360 degrees, depending on the polygon's shape. The sum of the exterior angles of a concave polygon can be greater than 360 degrees if the polygon has one or more reflex angles, which are angles greater than 180 degrees. In this case, the exterior angle at each vertex is less than the adjacent interior angle, so the sum of the exterior angles is greater than 360 degrees. On the other hand, if a concave polygon has no reflex angles, the sum of the exterior angles will be less than 360 degrees.

Explanation:

Answer 2

a. The sum of the interior angles of a regular polygon with n sides can be found using the formula (n-2) x 180 degrees. Using this formula, we know the sum of the interior angles of a pentagon is (5-2) x 180 = 540 degrees. Since the sum of the interior angles of a polygon increases by 180 degrees for each additional side, we can guess that the sum of the interior angles of a 17-gon would be (17-2) x 180 = 2700 degrees.

b. For concave polygons, the sum of the interior angles may not follow the same pattern as that of regular polygons. It is possible for the sum of the interior angles of a concave polygon to be greater or less than the sum of the interior angles of a regular polygon with the same number of sides. So, it is difficult to make an accurate guess without more information about the specific shape of the concave 17-gon.

c. The sum of the exterior angles of any convex polygon always equals 360 degrees because each exterior angle is supplementary to its adjacent interior angle. In other words, the exterior angle and the adjacent interior angle form a straight line, which is 180 degrees. Since there are n exterior angles in an n-sided polygon, the sum of all the exterior angles is n x 180 degrees. However, each exterior angle is counted once for each vertex, and there are n vertices, so we need to divide by n to get the total sum of exterior angles, which is (n x 180) / n = 180 degrees.

d. For a concave polygon, the sum of the exterior angles may be greater than or less than 360 degrees, depending on the shape of the polygon. In a concave polygon, some of the exterior angles will be greater than 180 degrees, which means that their adjacent interior angles will be less than 180 degrees. Since the sum of the exterior angles is equal to the sum of the adjacent interior angles, some of the exterior angles will need to be subtracted from 360 degrees to get the total sum of exterior angles. However, without more information about the specific shape of the concave polygon, it is difficult to make an accurate guess.