Final answer:
The graph of y = f(x) is a decreasing curve over the interval 8 ≤ x ≤ 13 and the region between the graph, the x-axis, and the lines x = 8 and x = 13 represents the area under the curve.
Step-by-step explanation:
The question asks us to consider a function f(x), which is decreasing over the interval 8 ≤ x ≤ 13. We are given that the definite integral of f(x) from x = 8 to x = 13 is equal to 65. This means that the area under the curve y = f(x) between x = 8 and x = 13 is equal to 65.
The region between the graph of y = f(x), the x-axis, and the lines x = 8 and x = 13 is a shaded region representing the area under the curve.
Since f(x) is decreasing over the interval 8 ≤ x ≤ 13, the graph of y = f(x) will be a decreasing curve from x = 8 to x = 13.