Sum of Interior Angles of Polygons

What is the SUM of the angle measures in a nonagon (9 sides)?

• 1440°
• 900°
• 1080°
• 1260°

Find the value of X.

• 100
• 120
• 125
• 130

Find the value of x.

• 110

• 90

• 130

• 120

What is the sum of the interior angles of the nonagon shown?

• 720° 
• 900° 
• 1080° 
• 1260° 

What is a regular polygon?

• all side lengths are the same length

• all angles are the same (equal in measure)

• only some side lengths are the same

• all side lengths are different

• only some angles are the same

Find the measure of one interior angle in each regular polygon. Round your answer to the

nearest tenth if necessary.

• A

• B

• C

• D

Find the measure of one interior angle in each regular polygon. Round your answer to the

nearest tenth if necessary.

• A

• B

• C

• D

Find the measure of one interior angle in each regular polygon. Round your answer to the

nearest tenth if necessary.

• A

• B

• C

• D

Find the measure of one interior angle in each regular polygon. Round your answer to the

nearest tenth if necessary.

• A

• B

• C

• D

What is the formula for the sum of interior angles in a polygon?

• 180(n−2)
• 180(n−2)÷n
• 360
• 360/n