Answer:
interval is the function decreasing.
Explanation:
Given : The graph of
is transformed to

To find : On which interval is the function decreasing?
Solution :
First we plot the graph of both the functions,
The graph of
is shown with black line.
The graph of
is shown with violet line.
Refer the attached figure below.
The graph shows the interval over which it is increasing or decreasing.
As we notice it is increasing on the interval

Decreasing on

Therefore,
interval is the function decreasing.