Constructing Parallel Lines

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Constructing Parallel Lines

• Objectives
• 1. Discover a method for constructing
  parallel lines.
• 2. Practice construction skills

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parallel lines - lines that lie in the same plane
and do not intersect
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Which pairs of lines are parallel?

• Not parallel.

1
Not parallel.
2
Parallel.
3
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Steps for Constructing Parallel Lines

• First, construct line m and point P close to but
  not on line m.

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1. Construct a perpendicular from point P to
line m. Label the point of intersection Q.
P
m
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1. Construct a perpendicular from point P to
line m. Label the point of intersection Q.
P
m
Q
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2. Select point R on line m and construct a
perpendicular ray starting at through point R
perpendicular to line m. Label new ray n.
n
P
m
Q
R
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3. With you compass, locate point S on line n so
that PQRS.
n
P
S
m
Q
R
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4. Construct line PS. This line is parallel to
line m.
n
P
S
m
Q
R