Final answer:
The possible values of a in the linear equation y = ax can be represented by the inequality a > 0.
Step-by-step explanation:
To determine the possible values of a in the linear equation y = ax, we need to analyze the end behavior of the equation. Given that at the left end of the graph, x approaches -∞, and y approaches +∞, and at the right end, x approaches +∞, and y approaches 0, we can infer that a is a positive value. Therefore, the inequality that represents the possible values of a is a > 0.