You are given two congruent triangles that have the same orientation. Using GeoGebra's tool, build a single rotation that takes the green triangle to the brown triangle.

Before you do anything:

Why can't the single move be a translation?

Why can't the single move be a reflection?

Play a little:
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Triangle ABC is the original triangle. See what happens when you change the lengths of the sides on triangle ABC.

Point D is fixed. You can rotate triangle DEF around D by moving point E.

Use the mouse to see that triangle DEF is indeed congruent to triangle ABC.

Use the upper right-hand corner reset icon, so that the triangles are back in their original position.
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