# Geometry

The sum of the interior angles of polygon is 1800. Find the number of sides in the polygon and, what do you call that polygon?

1. 👍 2
2. 👎 0
3. 👁 506
1. for n sides
exterior angle = 360/n
so interior angle = 180 - 360/n
sum of interior angles = n(180 - 360/n)
=180 n (1 - 2/n)
so here
1800 = 180 n (1 - 2/n)
10 = n - 2
n = 12 sides

1. 👍 2
2. 👎 0
posted by Damon
1. 👍 2
2. 👎 0
posted by Damon
2. duodecagon I mean

1. 👍 0
2. 👎 0
posted by Damon
3. glooks

1. 👍 0
2. 👎 0
posted by trill

## Similar Questions

1. ### math

find the sum of the measures of the intieior angles of each polygon. -hexagon -pentagon -quadrilateral -octagon -16-gon -27-gon The key is the sum of the measures. All of these figures have the same total number of degrees in

asked by kristen on March 12, 2007
2. ### math.

Each exterior angle of a regular polygon is 15 degrees. 1.Determine the number of sides of the polygon. 2.What is the sum of the interior angles? please help!!!!!!!! i'd love to help but i can't remember how to do those problems.

asked by Shay on February 25, 2007

Find the interior and exterior angle measurements of a polygon with this many sides: x=2y help? I don't want the answer, I just would like to know how to do this one. I don't see why a number of sides is being specified as an

asked by Emily on March 29, 2007
4. ### math

A regular polygon has the sum of the interior angles as 3240degrees . find the number of sides the polygon has.

asked by Nita on April 5, 2016
5. ### Maths

The sum of interior angles of an irregular polygon is 5040 .find the number of sides of the polygon

asked by Langton on September 27, 2017
6. ### goemetry

can the following formula to find the sum of the interior angles of a polygon be used on a concave polygon? 180(n-2) where n= the number of sides

asked by mike on February 24, 2010

1 Find the missing angle measure in the polygon A ] 77 B ] 87 C ] 97 D ] 107 i think its b 2 Find the sum of the interior angles in 10 - sided polygon A ] 1,260 B ] 1,440 c ] 1,620 d ] 1,800 i think its c or b 3 Find the measure

asked by melissa on December 4, 2015
8. ### Math

Each exterior angle of a regular polygon is 15 degrees. How many sides does the polygon have? and What is the sum of the interior angles? Since this is not my area of expertise, I searched Google under the key words "polygon

asked by Shay on April 4, 2007
9. ### Geometry

If the sum of the measures of the interior angles of a n-sided polygon is 1,0800, then set up a mathematical model to find the number of sides of the polygon.

asked by Summer. on June 3, 2015
10. ### Math

1. The measure of an interior angle of a regular polygon is 20 more than thrice the measure of its adjacent exterior angle. Find the number of sides of the polygon and its total number of diagonals. 2. Find the sum and difference

asked by Brianna on October 14, 2014

More Similar Questions