The object will hit the ground after aprroximately 4.6 seconds.
Approximately how long will it take to hit the ground?
We know that te graph shows the height of an object that has been launched off a 45 foot high wall. We want to find the time it takes to hit the ground, so we only need to see at which value in the horizontal value does the graph intercept it (the horizontal axis, y = 0, represents the ground in this case)
We can see that the x-intercept is at a value between 4.5 and 5, closer to 4.5.
We can estimate this to be 4.6
So we can say that the object will hit the ground after aprroximately 4.6 seconds.