MHB Sum of the measures of the interior angles of a heptagon

AI Thread Summary
The sum of the interior angles of a heptagon is 1260°, calculated using the formula (n-2)180°, where n is the number of sides. For a polygon with a sum of interior angle measures of 3600°, it has 22 sides, derived from rearranging the same formula. Each exterior angle of a regular octagon measures 45°, as the sum of exterior angles for any polygon is always 360°. The discussion emphasizes the importance of understanding these formulas for solving polygon angle problems. Accurate calculations are essential for determining angle measures in various polygon types.
yormmanz
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PLEASE HELP1.What is the sum of the measures of the interior angles of a heptagon?

A. 1260∘
B. 2520∘
C. 900∘
D. 1800∘

my answer is C

5.If the sum of the interior angle measures of a polygon is 3600∘, how many sides does the polygon have?
A. 22 sides
B. 20 sides
C. 18 sides
D. 10 sides

MY ANSWER ?

3.What is the angle measure of each exterior angle of a regular octagon?
A. 45∘
B. 135∘
C. 360∘
D. 1080∘

MY ANSWER ?
 
Mathematics news on Phys.org
couple of pieces of information to assist you ...

the sum of the interior angles of a convex n-gon is $(n-2)180^\circ$

the sum of the exterior angles of a convex n-gon is $360^\circ$
 
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