Final answer:
The domain of the exponential function f(x), which is graphed on a grid from 0 to 20, is best expressed by the inequality 0 ≤ x ≤ 20. It signifies that the function is defined for all real numbers within that range.
Step-by-step explanation:
The student's question is asking for the domain of a function that is displayed on a graph. The domain refers to the set of input values (x-values) for which the function is defined. Given the information that the function f(x) is an exponential function and is graphed between the values of 0 and 20, inclusive, the domain can be expressed as an inequality.
To represent the domain of the function f(x) for 0 ≤ x ≤ 20, we write the inequality as such. The exponential function is defined for all real numbers, but in this scenario, it is specifically restricted from 0 to 20. The inequality that best represents this domain is therefore 0 ≤ x ≤ 20. This means x can take any value starting at 0 up to and including 20.
When graphing such a function, it's important to label the x-axis with appropriate scale marks to indicate the domain's range. In an exponential decay graph, the y-value would typically decrease as x increases, but in the context of the question, the graph mentioned is a horizontal line, which suggests that the function's value remains constant across its domain.