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Meaning of a Function Presented Graphically

5.8.1 Meaning of a Function Presented Graphically

5.8.1 • Meaning of a Function Presented Graphically

Warm Up

Here is a graph of the accumulated rainfall in Las Vegas, Nevada, in the first 60 days of 2017.

Continuous graph with title of Accumulated Rainfall, Las Vegas, Nevada, x-axis label of day of the year 2017, and y-axis label of rainfall in inches. The x-axis goes from 0 to 60 in increments of 10, the y-axis goes from 0 to 1-point-6 in increments of 0-point-2. Each day has the amount of rain accumulated with no rain in the first 10 days.

Use the graph to support your answers to the following questions.

1.

Is the accumulated amount of rainfall a function of time?

Compare your answer:

Yes. For each number of days dd between 0 and 60, a certain amount of rain fell up to that time, so there is one particular value for the accumulated rain at any point in time.

2.

Is time a function of accumulated rainfall?

Compare your answer:

No. There was no rainfall in the first 10 days. This means that for the amount of rainfall 0 inches, or for the input value of 0, there are lots of times dd that could be the output.