1.3 Points Lines and Planes

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1.3 Points Lines and Planes
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Lets Review

• Use inductive reasoning to finish the sentence
• The sum of three consecutive integers is always
  three times______________

Make some examples 34512 ( 3?) 45615
(3?) 56718 (3?) 67821 (3?) What is the
pattern? What is the answer?
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• Find a counter example to this conjecture
• If the product of two numbers is positive, then
  the two numbers must both be positive
• Any ideas for counter examples?

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1.3

• Point
• has not dimension. it is represented by a small
  dot.
• A or point A

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• Line
• has 1 dimension. It extends without end in two
  directions. It is represented by a line with two
  arrowheads.

l
line BC OR line l
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• Plane
• has two dimensions. It is represented by a shape
  that looks like a floor or a wall. You have to
  imagine that it extends without end.

Plane M
M
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Postulates

• Three points determine a Plane
• through any three points not on the same line
  there is exactly one plane
• Two points determine a line
• through any two points there is exactly one line

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• Coplanar lines
• lines that lie on the same plane
• Coplanar points
• points that lie on the same plane
• Collinear points
• points that lie on the same line

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