IM Geo.1.14 Lesson: Defining Rotations
For each figure, which pair of angles appears congruent? How could you check?
Your teacher will give you either a problem card or a data card. Do not show or read your card to your partner.
If your teacher gives you the data card: If your teacher gives you the problem card:
Do not show or read your card to your partner.
Use the applet below:
Draw a segment. Label the endpoints and .
What kind of triangle did you draw?
What other properties do you notice in the figure? Explain your reasoning.
Use the applet below:
Draw a segment. Label the endpoints and .
What kind of triangle did you draw?
What other properties do you notice in the figure? Explain your reasoning.
You constructed an equilateral triangle by rotating a given segment around one of its endpoints by a specific angle measure.
An equilateral triangle is an example of a regular polygon: a polygon with all sides congruent and all interior angles congruent. Try to construct some other regular polygons with this method.