Slope = rise/run =[y2-y1]/[x2-x1]
1) slope = [90 - 30] / [12 - 4] = 60 / 8 = 15/2
2) slope = [75 - 30] / [10 - 4] = 45 / 6 = 15 / 2
The slopps are equal.
Answer:
(-infinity, inifinty)
Step-by-step explanation:
the domain should be all real numbers of this quadratic
For this case we have to by definition, if two lines are perpendicular then the product of its slopes is -1.
That is to say:

We have the following equation:

So:

Thus:

Thus, a line perpendicular to the given line must have slope 
Option A:

It is not perpendicular!
Option B:

If it is perpendicular!
Option C:

It is not perpendicular!
Option D:

It is not perpendicular!
The correct option is option B
ANswer:
Option B