I think it would be most likely A the first one.
Answer:
C) They are perpendicular lines.
Step-by-step explanation:
We first need to find the slope of the graph of the lines passing through these points using:

The slope of the line that passes through (−12, 15) and (4, −5) is


The slope of the line going through (−8, −9) and (16, 21) is



The product of the two slopes is

Since

the two lines are perpendicular.
The answer is 36.
Because 20% of 36 is equal to 7.2
And 36 - 7.2 = 28.80