We start at `t = 0` since negative values of time have no practical meaning here.
We choose values `0.5` seconds apart (if we were to use `t = 1\ "s"` intervals, we would not see enough detail on the graph).
Graph of projectile (parabola).
This shape is called a parabola and is common in applications of mathematics.
(1) This graph is height against time. The ball went straight up, not forward. (Our graph may give the impression the ball moved in the x- direction as well as up, but this was not the case.)
(2) We could have written the function in this example with h(t) rather than just h. The following 2 equations mean the same thing.
h = 2 + 9t − 4.9t2
h(t) = 2 + 9t − 4.9t2