Rotations: Investigation

Play around with the items on the screen below and observe what happens so that you are ready to answer the questions below. Drag the green slider. Drag the pre-image points (A, B, C, or D) Drag point E

What did you notice about the lowest and highest numbers on the green slider? Why do you think these numbers are meaningful? (Why these numbers and not 512 or 2,035?)

When you slide the green slider into the negative numbers, what direction is the image turning?

Rotate the figure using the positive angles on the green slider. Try changing the location of point A or the pre-image points. Think about what you are noticing to answer the remaining questions.

What does point A have to do with the three circles in the diagram?

Is it possible for one of the image points to remain in place (not move) during the rotation? If so, what needs to happen in the diagram?

What does a 180 degree rotation look like? (Where is the image? What direction is it pointing? Is it upside down?)