In this video segment, participants discuss some of the vocabulary of geometry. Watch this segment after you have completed Problems D1-D3 and compare your thinking with that of the onscreen participants.
What are some of the difficulties the participants ran into while trying to define a point and a line? How are your descriptions similar to or different from those of the onscreen participants?
If you are using a VCR, you can find this segment on the session video approximately 20 minutes and 48 seconds after the Annenberg Media logo.