Download Parallel Lines and Planes Chapter 3 Geometry Honors Page 73

Parallel Lines and Planes
Chapter 3
Geometry Honors
Page 73
Objectives:
1. Distinguish between intersecting lines, parallel lines, and skew lines.
2. State and apply the theorem about the intersection of two parallel
planes by a third plane.
3. Identify the angles formed when two lines are cut by a transversal.
4. State and apply the postulates and theorems about parallel lines.
5. State and apply the theorems about a parallel and a perpendicular to
a given line through a point outside the line.
Topics
3.1 Definitions
3.2 Properties of Parallel Lines
3.3 Proving Lines Parallel
3.4 Applying Parallel Lines to Polygons
3.5 Angles of a Polygon
3.6 Inductive Reasoning
Definitions
Lesson 3.1
Geometry Honors
Page 73
Objectives
1. Distinguish between intersecting lines,
parallel lines, and skew lines.
2. State and apply the theorem about the
intersection of two parallel planes by a third
plane.
3. Identify the angles formed when two lines
are cut by a transversal.
Parallel lines
Parallel Lines are coplanar lines that never
intersect. Two non-vertical lines are parallel if
and only if they have the same slope.
Skew lines
Two lines that do not intersect but are not
parallel. They are lines that are not both in
the same plane.
Parallel planes
Two planes that do not intersect
Transversal
A line that passes through two or more other
coplanar lines at different points.
Alternate interior angles
Alternate Interior Angles are created where a
transversal crosses two (usually parallel) lines.
Each pair of these angles are inside the
parallel lines, and on opposite sides of the
transversal.
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2
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Same-side interior angles
Two interior angles on the same side of the
transversal.
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Corresponding Angles
When two lines are crossed by another line
(the transversal), the angles in matching
corners are called corresponding angles.
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3
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2
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Parallel Planes Theorem
If two parallel planes are cut by a third plane,
then the lines of intersection are parallel.
Homework
Page 76 - 77
Problems
1 - 41 odd