Plane Geometry

1
Plane Geometry

• Discovering Geometry
• An Investigative Approach
• Michael Serra, 2003
• Mr. Gilman
• Room 243
• Periods B and G

2
Chapter 1 Introducing Geometry

• Definitions of many terms used in Geometry
• Introduction to notation used in Geometry
• Practice in visual thinking
• Practice in applying algebra skills
• Translating between diagrams and descriptions

3
Building Blocks of Geometry

• A few terms to get things started
• Point
• Line
• Plane
• Space
• These are undefined terms
• We can agree on their meaning, but using a term
  to define itself is not good practice!

4
Building Blocks of Geometry

• Collinear points
• Two or more points on the same line
• Coplanar points
• Two or more points on the same plane
• Line segment
• The part of a line between two endpoints
• Ray
• The part of a line to one side of an endpoint

5
Building Blocks of Geometry

• Midpoint of a line segment
• The point on a segment equidistant from both
  endpoints
• Measure of a line segment
• The distance between endpoints of the segment
• Congruent line segments
• Two line segments with the same measure

6
Building Blocks of Geometry

• Coordinate Geometry
• Geometry on a coordinate plane
• Midpoint formula
• Given two points A(x1, y1) and B(x2, y2), on a
  coordinate plane, the midpoint M of the line
  segment between points A and B has coordinates
  x1 x2 y1 y2

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