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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Equation of Locus - Parabola
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Reflection = 180° Rotation about a Line
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Geom. & Alg.: Exponential Functions & Logarithms
i - geometry probabilities
Angle Bisector Proportions
deslizadores6
Regular and star-heptagons

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