Activity 4.1 Interior and Exterior Angles of Polygons
YOUR TASK
Explore and identify the relationships between the angles formed by intersecting lines.
Determine if the statements of relationships between angles is ALWAYS TRUE or ALWAYS FALSE
This GeoGebra applet shows a quadrilateral ABCD with the measure of its interior angle shown.
To explore, click the button to show the figure when the sides are extended. You can also change the figure by dragging any of the points A, B, or C. Each time you drag any of the points, you will have a different set of angle measurements.
To identify the relationships among the angles, record the measurements of the angles in the table.
Generate sets of measure for interior and exterior angles of quadrilateral ABCD.
TRUE or FALSE, JUSTIFY
For each of the statement below,
Write TRUE if the statement is always true. Then, justify your answer using the data in the table.
Write FALSE if the statement is always false or not true. Then, justify using a counterexample from the table.
Sum of interior angles
The sum of the four interior angles of the quadrilateral is 360 degrees. ALWAYS TRUE or ALWAYS FALSE? Justify your answer with examples from the table.
Sum of a pair of interior and exterior angles with common vertex
The sum of a pair of interior and exterior angles in quadrilateral ABCD is 180 degrees. ALWAYS TRUE or ALWAYS FALSE? Justify your answer with examples from the table.
Pair of interior angles
The sum of any pair of interior angles in quadrilateral ABCD is 180 degrees. ALWAYS TRUE or ALWAYS FALSE? Justify your answer with examples from the table.
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Co-developer
Erlina Ronda