This document provides geometry definitions and examples for Lesson 18. It defines lines, rays, segments, and angle types like acute, obtuse, right, and straight. It also defines parallel and perpendicular lines and provides examples of using a protractor to measure angles. Examples are given to identify lines, rays, segments, parallelism, perpendicularity, and angle measurements.

1. lesson 18.notebook September 24, 2012
Lesson 18
*Geometry Information:
segment B line
A
ray B
B
A A
C
parallel lines perpendicular lines
B B
A A
D D
C
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2. lesson 18.notebook September 24, 2012
FYI...
acute angle­­> degrees in a circle­­>
obtuse angle­­> semi­circle­­>
right angle­­> quarter­circle­­>
straight angle­­>
linear pair­­>
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3. lesson 18.notebook September 24, 2012
protractor
(Used to
measure
and/or draw
angles!!)
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4. lesson 18.notebook September 24, 2012
Examples ­ Lesson 18
pg. 117
A) line
B) ray
C) segment
D) parallel
E) perpendicular
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5. lesson 18.notebook September 24, 2012
F) acute angle
G) obtuse angle
H) right angle
I) straight angle
J) 135 degrees
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