Collinearity, Betweenness,

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Collinearity, Betweenness, Assumptions Geometry
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Collinear Points Points on the same line.
A, B, and C are COLLINEAR points.
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Non-Collinear Points Points not on the same
line.
A, B, and C are Non-COLLINEAR points.
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Betweenness Points must lie on the same line and
AB BC AC.
Y is not between X and Z because the points are
not on the same line.
B is between A and C
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Triangle Inequality The sum of two sides of a
triangle must always be greater than the third
side.
AB 3 BC 8 AC 11
Triangle cant exist!
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Triangle Inequality The sum of two sides of a
triangle must always be greater than the third
side.
5 7 gt x 12 gt x AND 5 x gt 7 x gt
2 AND 7 x gt 5 x lt -2
So, 2 lt x lt 12
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Assumptions From A Diagram.
Can Assume 1. Straight Lines and
Angles 2. Collinearity of Points 3. Betweennes
s of Points 4. Relative Position of Points
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Assumptions From A Diagram.
Can Not Assume 1. Right Angles 2. Congruent
Segments 3. Congruent Angles 4. Size of An
Angle