[Edu-sig] Your dream Linear function class

[Kevin Driscoll]

Hi y'all,

My Pre-Calc peoples are finishing up a refresher unit on Linear
Functions.  This week, they are working on a "mini-text" with
definitions, examples, tips, and tricks.  They'll be wiki-izing this
work next week.  Each unit will follow the same pattern as a way to
build a "math portfolio" for the year.

I am planning to take them into Pythonic PreCalc after each unit to
add a new class to their growing library.  These will be reproduced on
the wiki and in their portfolios as well.

So what would your ideal Linear Function class contain?

Methods:
 - return slope
 - return x-int
 - return y-int
 - maybe one that takes another Line and returns the coords for their
intersection?
 - return expression (e.g. mx + b)

About a third of the students have studied Python with me before in CS
so they can help bring the rest along.  (We are my smallest class at
15 11th and 12th graders.)  We aren't afraid of import.  Is there an
easy graphing solution?

Getting psyched for Quadratics and Complex numbers in October!
Kevin