It's x=-5. It is a vertical line, and vertical lines have a consistent x coordinate. Since it passes through (-5,0), you take the x-coordinate of this point.
Answer:
1. diagram in the attachment
2. AB = 32.3 ft
Step-by-step explanation:
2. from the diagram:

A straight line extending from the center of a circle or sphere to the circumference or surface.. of a circle is a half the diameter.