http://www.ck12.org Chapter 6. Polygons and Quadrilaterals
6.1 Angles in Polygons
Learning Objectives
- Extend the concept of interior and exterior angles from triangles to convex polygons.
- Find the sums of interior angles in convex polygons.
- Identify the special properties of interior angles in convex quadrilaterals.
Review Queue
- Find the measure ofxandy.
a.b.2.
a. Findw◦,x◦,y◦, andz◦.
b. What isw◦+y◦+z◦?
c. What two angles add up toy◦?
d. What are 72◦, 59 ◦, andx◦called? What arew◦,y◦, andz◦called?Know What?Below is a picture of Devils Postpile, near Mammoth Lakes, California. These posts are cooled lava
(called columnar basalt) and as the lava pools and cools, it ideally would form regular hexagonal columns. However,
variations in cooling caused some columns to either not be perfect or pentagonal.
First, defineregular in your own words. Then, what is the sum of the angles in a regular hexagon? What would each
angle be?