Transversal with two Parallel Lines

Please watch video and construct app below video.
Construct the two nonparallel lines (black lines) and the transversal line. After creating the construction move any point on one of the black lines.
After doing the construction on the GeoGebra app, move any point on the lines. What do you notice?

What type of angles are congruent?

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What type of angles are supplementary?

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