Download Geometry 3-1 Parallel Lines and Transversals

Geometry 3-1 Parallel Lines and Angles
• Parallel Lines- lines that never intersect
• Symbol: ||
• Perpendicular Lines- lines that intersect
and make right angles
• Symbol: ┴
• Parallel Planes- planes that do not
intersect
• Skew lines- lines that are not coplanar, are
not parallel, and do not intersect.
Examples
Identify each of the following.
a. a pair of parallel segments
BF || EJ
b. a pair of perpendicular
segments
BF ┴ FJ
c. a pair of skew segments
BF and CD
Vocabulary
• Transversal: A line that intersects two lines at
different points.
Transversal line
Vocabulary
• Corresponding angles: the same angle location but for a
different intersection.
congruent
A B
C D
A B
C D
Vocabulary
• Alternate Interior Angles: opposite sides of the transversal
and between the parallel lines.
congruent
A
B
B
A
Vocabulary
• Alternate Exterior Angles: opposite sides of the
transversal and outside the parallel lines.
congruent
A
B
B
A
Vocabulary
• Same-Side Interior: same side of the transversal and
between parallel lines.
supplementary
A B
A B
Vocabulary
• Same-Side Exterior Angles: same side of the transversal
and outside the parallel lines.
supplementary
A
B
A
B
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