Use the graph of each function to estimate the intervals on which the function is increasing or decreasing.
Decreasing in the interval $(-2.5,1)$
Increasing in the intervals $(-\infty,-2.5)$ and $(1,+\infty)$
this is pretty straightforward. Based on the given graph, the function is decreasing from negative 2.5 toe one and we can see it's increasing at two points from negative infinity to negative 2.5 and from one to positive infinity. Those are the two points at which it is increasing.