Question

(a) determine the measure of an interior angle of the named regular polygon.
(b) if a side of the polygon is extended, determine the supplementary angle of an interior angle.

quadrilateral

(a) the measure of each interior angle of a regular quadrilateral is 180°.

Explanation:

Calculate the interior angle of a regular quadrilateral

Using the Polygon Angle Sum and Regular Polygons knowledge points

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Calculate the supplementary angle of the interior angle

Using the Supplementary Angles knowledge point

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Answer:

Question 1

The measure of each interior angle of a regular quadrilateral is 90 degrees.

Question 2

If a side of the polygon is extended, the supplementary angle of an interior angle is 90 degrees.