Lesson 86. Properties of Parallel Lines

T6-criterion for parallel lines

[bgcolor=orange] If two lines are intersected by a third line, and alternate interior (or exterior) angles are equal, then the original two lines are parallel. [/bgcolor]

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Rotating Plane Figures to Form Solids
Perpendicular Lines: Quick Exploration
GeoGebra 3D Modeling Workshop (March 8 2024)
Angle Addition Postulate (V2) - Integer Solutions

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Internal forces - stair beam
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The Sin Function and Key Points
P Plot Ordered Pair Non Axis
Investigation 2.1 (Perfect vs. Tilted Squares)

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