Aki introduced us to a specific problem on a 7 X 7 geoboard. See 7x7geoboard.doc. Two points were labeled. Calling the bottom left peg (1, 1), A had coordinates (3, 2) and B had coordinates (6, 3). Segment AB was drawn. The instruction was to find all of the isosceles triangles that could be made with AB as a side. We worked on this in groups and came up with nine distinct solutions. Aki helped us categorize them in terms of which pair of sides were congruent. See Solutions to Isosceles Triangle Problem.
Back to: Class Notes
PCMI@MathForum Home || IAS/PCMI Home
With program support provided by Math for America
This material is based upon work supported by the National Science Foundation under Grant No. 0314808.