Polygon Angle Sum - Activity A Gizmo

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Polygon Angle Sum - Activity A

Derive the sum of the angles of a polygon by dividing the polygon into triangles and summing their angles. Vary the number of sides and determine how the sum of the angles changes. Dilate the polygon to see that the sum is unchanged.

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Assessment Questions (3):

What is the sum of the measures of the interior angles of a heptagon?
- A. 900°
- B. 1260°
- C. 1620°
- D. 2520°
If the angle measures of the interior angles of a pentagon are 130°, 94°, 109°, 112°, and x°, find x.
- A. x = 95
- B. x = 105
- C. x = 108
- D. x = 275
What is the angle measure of each interior angle of a regular decagon?
- A. 36°
- B. 108°
- C. 144°
- D. 1080°

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