To determine where the function $h(x)$ is decreasing, we need to identify the intervals where the graph of the function is moving downward as we move from left to right.

Looking at the quartic polynomial function in the image:

1. The graph decreases in two regions:
   • First, the graph decreases from its peak at $x \approx -4$ to a minimum at $x \approx 1$.
   • Then, after a small increase, the graph decreases again from $x \approx 3$ and continues to decrease beyond the visible portion of the graph.

Thus, the function $h(x)$ is decreasing on the intervals: $(-4, 1) \cup (3, \infty)$

Would you like more details or have any questions?

Here are 5 related questions to extend your understanding:

1. What are the conditions for a function to be decreasing on an interval?
2. How do we determine the critical points of a polynomial function?
3. What is the significance of local minima and maxima in the context of increasing and decreasing intervals?
4. Can you find the derivative of this quartic function and use it to confirm where the function is decreasing?
5. How do polynomial degrees affect the number of turning points?

Tip: A function decreases on intervals where its derivative is negative.