Download Parallel Lines and Transversals

Chp. 5.3 ­ Parallel Lines and Transversals
February 14, 2013
Date:
Chapter: Chapter 5:3 ­­> Parallel Lines and Transversals
Objectives: Identify angles formed by parallel lines and
transversals
Identify and use properties of parallel lines.
Integrated Math II
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Chp. 5.3 ­ Parallel Lines and Transversals
February 14, 2013
Notes:
*Parallel Lines = Coplanar lines that do not intersect.
*Parallel Planes = Planes that do not intersect.
*Skew Lines = Noncoplanar lines that do not intersect and are not parallel.
*Transversal = A line that intersects two other coplanar lines.
*Alternate Interior Angles = Two angles that are inside the two lines on opposite sides of the transversal.
*Same­Side Interior Angles = Aka Consecutive Interior Angles; they are angles that are on the same side of hte transversal and inside the two lines.
*Alternate Exterior Angles = Two angles that are outside the two lines on opposite sides of the transversal.
*Corresponding Angles = Two angles that are in teh same position but on different lines.
Postulates 5 & 6
Postulate 5 = If two parallel lines are cut by a transversal then corresponding angles are congruent.
Postulate 6 = If two lines are cut by a transversal so that corresponding angles are congruent then the lines are parallel.
Statements 5A­5D
5A = If two parallel lines are cut by a transversal then alternate interior angles are congruent.
5B = If two parallel lines are cut by a transversal then alternate exterior angles are congruent.
5C = If two lines are cut by a transversal so that alternate interior angles are congruent then the lines are parallel.
5D = If two lines are cut by a transversal so that alternate exterior angles are congruent then the lines are parallel.
Integrated Math II
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Chp. 5.3 ­ Parallel Lines and Transversals
February 14, 2013
Examples:
Ex. 1 ­ Identify the angle relationships.
a) Alternate Exterior Angles
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2
3 4
5 6
b) Alternate Interior Angles
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c) Same­Side Interior Angles
d) Corresponding Angles
Ex. 2 ­ Line A is parallel to line B. Name the postulate that makes a­c true.
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3
6
5
7
a) <2 = <6
Integrated Math II
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2
4
A
B
b) <4 = <5
c) < 1 = <8
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Chp. 5.3 ­ Parallel Lines and Transversals
February 14, 2013
Homework:
p. 204 (#13­29, 32­34)
Integrated Math II
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