To determine the domain of the linear function described in the graph, we note that it is a solid line that extends from the point \((-9, -5.3)\) on the left to the point \((7.5, 4.5)\) on the right. Since the line is solid, it includes both endpoints.
Thus, the domain of the function is all \(x\) values from \(-9\) to \(7.5\) inclusive, which can be described by the inequality:
\[-9 \leq x \leq 7.5\]
However, since the provided options do not include \(7.5\) specifically, and since the closest option that accurately reflects the left endpoint is:
\[-9 \leq x < 7\]
This cannot be correct either. The best fitting response from the options provided would be:
\[-9 \leq x \leq 7\]
Thus, if careful, the answer should reflect that the function exists in this interval, but if limited to available responses according to provided disparities, the most concise representation while remaining inclusive is:
x ≥ -9 (implying from that point onward, but should acknowledge a range extending toward \(+\infty\) accurate to initial details from graph confines).
Nonetheless, without leaning on selectivity, describing the real maximal content details remains paramount adhering toward actual usage in analytical value concerns in function directionally engaged.