The Drummond Geometry Forum

I have noticed that several examples and questions were addressed to the closed 5/3 lines in lesson 2, section 4. It is interesting to note that
the closed 5/3 lines were not even covered in section 1 of lesson 2. I guess they were left out by mistake.

DY

I don't recall what we were thinking at the time, but it was probably that we had explained the concept of the closed line and that was sufficient. But, might have just forgottten.