Introduction to Geometry: Points, Line, and Planes

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Introduction to Geometry Points, Line, and
Planes
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Basic Geometric Figures
A point is a location in space. It has no size
or thickness.
Point -
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Basic Geometric Figures
A line is a series points that extends in two
directions without end.
Line -
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Basic Geometric Figures
A plane is a flat surface. It has no thickness.
It continues without end in all directions
Plane -
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Basic Geometric Figures
Line Segment or Segment -
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Basic Geometric Figures
Ray -
A ray is a part of a line. It has exactly one
endpoints. Name its endpoint first.
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Example 1
Name each figure in the diagram.
a. Name four points.
H, K, T, and W
b. Name four different segments.
d. Name five different rays.
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Intersecting, Parallel and Skew Lines
Two lines intersect if they have exactly one
point in common.
Two lines that lie in the same plane and do not
intersect are parallel. You use the symbol to
indicate is parallel to
Skew lines are lines that do not lie in the same
plane. They are not parallel and they do not
intersect.
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Intersecting, Parallel and Skew Lines or Planes
Think of your classroom. Answer the following
questions
1) Name two planes that are parallel.
Floor and ceiling front and back walls etc.
2) Think of two planes that intersect (floor and
the front wall), what geometric figure does the
intersection make?
A line (the intersection of two planes is always
a line)
3) Think of two intersecting lines. What
geometric figure is at the intersection?
A point (the intersection of two lines is always
a point)