Billy kicks a soccer ball off the ground after taking a quick running start. The graph below shows the height of the ball. What do(es) the solution(s) to the function represent?

From the graph, the solutions of the function represents the instants in which the ball hits the ground.
In the graph, we have that:
The solutions are x = 1 and x = 5, which represents the instants in which the ball is in the ground.
For a similar problem, in which we find the times in which an object hits the ground, you can check https://brainly.com/question/16840613