what the graph depicts is that an increase in velocity with time at constant acceleration is a straight line graph
that is, increase in velocity will lead to equal increase in time at constant acceleration
likewise, for deceleration, it's the same thing, only that the values changes to negative in this case as a result of negative velocity
but the graph is actually different for deceleration
this is a graph for deceleration
however, it is worthy of note that the slope is actually the value of acceleration
[tex]\begin{gathered} a=\frac{v_2-v_1}{t_2-t_1} \\ a=\frac{dV}{dT} \end{gathered}[/tex]
