Interior Angle Sums in Polygons

Last updated over 3 years ago
11 questions
Please complete each of the below examples to the best of your ability.

Use one of the following two strategies for determining the interior angle sum for a polygon:

1) Draw diagonals to create triangles, which have an interior angle sum of 180⁰. In the blue pentagon below, two diagonals create three triangles → 180 • 3 = 540⁰ interior angle sum


2) Use the formula method >>> (n − 2) • 180, where n = the number of the sides. The blue quadrilateral below has four sides. Substitute 4 in for n (4 − 2) • 180 = 360⁰ interior angle sum


You can also use your notes and/or the following videos for assistance as needed.
Required
1

Find the measure of the fourth interior angle.

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1

The figure below displays a hexagon. What is the measure of angle x?

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1

Using a method of your choice, determine the sum of the interior angles within this regular nonagon.


Please type just the number!

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1

Using a method of your choice, determine the sum of the interior angles within this regular heptagon.


Please type just the number!

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2

Using a method of your choice, determine the sum of the interior angles within this irregular hexagon. Then, solve for the measure of angle x.


Please type just the number!

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2

Using a method of your choice, determine the sum of the interior angles within this irregular heptagon. Then, solve for x.


Please type just the number!

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2

Determine the measure of each individual interior angle in a regular hexagon (six-sided figure).


Please type just the number!

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2

Determine the measure of each individual interior angle in a regular dodecagon (12-sided figure).


Please type just the number!

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2

Find the number of sides in a polygon whose sum of the interior angles is 1800.

Please type just the number!

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2
The border of a Susan B. Anthony dollar is in the shape of a regular polygon.

a) The polygon has _______ sides.

b) The measure of each interior angle of the border is _______ degrees. Round your answer to the nearest degree!
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