According to the given graph, we have two increasing intervals and one decreasing interval.
Remember, the function increases when y-values increase while x-values increase. On the other hand, the function decreases when y-values decrease while x-values increase.
Having said that, we can define the following intervals.
Where I show where the function increase, and D shows where the function decreases.
A second way to express the intervals is as follows.
The function h increases: