This geometry video tutorial provides a basic introduction into the exterior angle inequality theorem. It explains how to use it in a two column proof situation.
Triangle Congruence - SSS, SAS, ASA: https://www.youtube.com/watch?v=jWHOF6cFbpw
CPCTC - 2 Column Proofs With Triangles:
https://www.youtube.com/watch?v=eq1frp_ZyP8
Hypotenuse Leg Theorem - HL Postulate:
https://www.youtube.com/watch?v=DKSTjS0n3mY
Detour Proofs - Double Triangle Congruence:
https://www.youtube.com/watch?v=1HOrB5yvEl0
The Midpoint Formula:
https://www.youtube.com/watch?v=pzDfd8NXRXk
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Missing Diagrams - 2 Column Proofs:
https://www.youtube.com/watch?v=IaqzuGweGZ8
Right Angle Theorem - SSS & SAS:
https://www.youtube.com/watch?v=FRbFMp8mg1s
Perpendicular Bisector Theorem:
https://www.youtube.com/watch?v=xyNBZuUjmSE
Altitude, Median, Midpoint & P. Bisector:
https://www.youtube.com/watch?v=SyzkgBjXtIs
Parallel & Perpendicular Lines - Slope:
https://www.youtube.com/watch?v=bq3fKZVTflU
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Indirect Proofs - Example Problems:
https://www.youtube.com/watch?v=GawWGpnjy1c
Proving Parallel Lines With Proofs:
https://www.youtube.com/watch?v=0eYzPVgylO8
The Exterior Angle Theorem:
https://www.youtube.com/watch?v=ndqxxAUDF5Y
Polygons:
https://www.youtube.com/watch?v=E_-3ulbtcLk
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https://www.video-tutor.net/
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