[Tutor] slope(x1, y1, x2, y2)???

[Ulrich]

Hello again all and sorry for the bother but I'm having a bit of trouble
here.

Still busy with the "How to Think Like a Computer Scientist" book and am
at chapter 5 busy with unit testing.

I'm having problems with the exercise #3 on
http://openbookproject.net//thinkCSpy/ch05.xhtml#auto9 . I have
absolutely no clue how to get all my values to return "OK" in the unit
test.

Any help would be appreciated, I do not want to continue the courses if
I don't understand something.

Thanks!