First, find the points for A and B.
A: (-9, 4)
B: (5, 4)
Because both of the points have the same y-coordinate value, we don't have to use the distance formula.
Simplify, find the difference between the x-coordinate values and find the absolute value of the difference.
|5 - (-9)| = |14| = 14
So, 14 units is the answer.