For the equation of the line expressed as Ax + By + C = 0, the value of the slope (m) is calculated by -A / B. For perpendicular lines, the slope of one should be the negative reciprocal of the other. From the choices given, the lines that are perpendicular is Option A.
The x intercept represents the maximum number of books he can buy
-2 is the answer when i figured out the problem
Rise over run.
The rise is 3
The run is 1
So the slope is 3/1