Two Parallel Line Reflections

1) Which polygon is the reflection of which over which line? How do you know?

2) Play with moving the lines. If you consider moving from the purple to the orange, what motion is it? Is it always the same?

3) How does changing the distance between the lines affect the composition? How does changing the slope of the black line affect the composition? What if you drag the black line without changing its slope?

4) Show the translation. Investigate the relationship between the double reflection and the matching translation. What did you find? How did you find it?

5) Pose another question to address with this sketch:

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John Golden, Created with GeoGebra