To determine on which interval the function is decreasing and non-linear, let's analyze the graph:

1. Decreasing intervals: A function is decreasing when its slope is negative (i.e., the graph goes downward as $x$ increases).

2. Non-linear intervals: A function is non-linear when its graph is not a straight line.

Analysis of the Graph:

• From $x = -9$ to $x = -3$, the graph appears to be decreasing in a straight line (linear).
• From $x = -3$ to $x = 0$, the graph is also decreasing but curves downward, which indicates that it is non-linear in this interval.
• From $x = 0$ to $x = 3$, the graph increases.
• From $x = 3$ to $x = 9$, the graph is increasing, and it is not relevant since we are looking for a decreasing interval.

Conclusion:

The function is decreasing and non-linear on the interval $-3 < x < 0$.

Thus, the correct answer is:

$\boxed{-3 < x < 0}$

Would you like further details or have any questions?

Here are 5 related questions to expand your understanding:

1. How can we distinguish between linear and non-linear functions visually?
2. What are the key features of a function’s graph to identify intervals where it is increasing or decreasing?
3. How does the slope of a function relate to its increasing or decreasing behavior?
4. Can a function be non-linear and still have increasing or decreasing sections?
5. What is the difference between concave up and concave down behavior on a graph?

Tip: When analyzing graphs of functions, always focus on the slope (positive or negative) and whether the graph forms straight lines (linear) or curves (non-linear).