Post #6

More about angles

Supplementary Angles- Two angles whose sum of measure is 180 degrees (they do not need to be adjacent)
Examples: 140 + 40=180
Complementary Angles- Two angles the sum of whose measures is 90 degrees. Each angle is a compliment of the other. (they do not need to be adjacent)
Example:  60+30= 90
Vertical Angles- Created by intersecting lines which are pairs of angles whose sides are two pairs of opposite rays. VERTICAL ANGLES ARE CONGRUENT.
Transversals and Angles- Transversal line is any line that intersect a pair of lines in a plane.



Interior angles: <2, <3, <7, <8
Exterior angles: <1, <4, <5, <6
Alternate angles: <2 and <8, <3 and <7
Alternate exterior angles: <1 and <5, <4 and <6
Corresponding angles:
<1 and <2, <4 and <7, <8 and <5, <3 and <6





How to find the sum of the interior angles of a regular n-gon:
n-2(180)

Example:
Decagon
(10-2)(180)
(8)(180)
1440

To get the measurement of each individual interior angle divide the sum of the interior angles by n
1440/10=144



How to find the sum of exterior angles is to then take 180 minus the individual angle and then times by n
180-144=36
36(10)=360