Final answer:
The function that matches the given graph, which is a horizontal line at y = 20 from x = 0 to x = 20, is a constant function represented by f(x) = 20.
Step-by-step explanation:
The provided information suggests that the student needs to write a function for a graph with certain characteristics. It's implied that the graph is a horizontal line, which is a constant function. Considering the function f(x) = 20 for 0 ≤ x ≤ 20, the graph would be a straight horizontal line at the y-coordinate of 20 for all x-values from 0 to 20 inclusive. This is because a horizontal line indicates that the y-value (output of the function) remains the same regardless of the x-value (input of the function).
Creating a Horizontal Line Function
To match a horizontal line graph, you would use a constant function. A constant function has the form f(x) = c, where c is a constant value. So for the given graph where the line is at y = 20, the function is f(x) = 20. This function indicates that no matter the value of x, as long as it's between 0 and 20, the value of f(x) will always be 20.