1. Which line is the flattest (or is less steep)? Why?

Question

a.y = 5x -6
b.y = 5x + 6
c.y = x - 3
d.y = x + 3

I think this question has been aswered a couple times, but I'll try again.
The slope is given by the number before the x varible. The first two choices have the same slope of 5. The last two choices also have the same slope, which is 1.
There is 'no' "flattest" line among the choices because the last two have the same slope.
The question is phrased incorrectly and does not have a single choice. Both c and d are correct.

Sorry I left out the 1/2x for letter C.Would it then be D?

No, it would then be C. because 1/2 < 1

Oh ok thanx