Answer:
6. (a) -9 < x ≤ 2
7. (c) All real numbers
Explanation:
You want the domains of the two function graphs.
Domain
The domain of a function is the set of x-values for which it is defined. It is the horizontal extent of the graph.
6. Line segment
The line segment graph has an open circle at x = -9. This is sufficient to tell you the correct answer choice is ...
-9 < x ≤ 2
7. Parabola
The arrows on the ends of the curve tell you the curve extends horizontally to -∞ and to +∞. The curve is defined on a domain of ...
All real numbers
__
Additional comment
The right end of the segment in problem 6 has a solid dot at x=2. This tells you that x=2 is right end point of the domain. This, too, is sufficient to tell you that the first answer choice is the correct one.