Question

determine the domain on which the following function is decreasing.

Explanation:

Step1: Identify decreasing interval

A function is decreasing when its graph falls as we move from left to right. Observe the parabola's vertex at $x=-4$; the graph decreases from $-\infty$ to this vertex.

Step2: Write the domain interval

The domain where the function decreases is all real numbers less than $-4$.

Answer:

$(-\infty, -4)$