Question

At 5:00 p.m., Antonio turned on the oven. While the oven preheated, the temperature in the oven increased from 72°F to 400°F over a 10-minute period. The oven remained at 400°F for 45 minutes until Antonio turned it off. It took 60 minutes for the temperature in the oven to cool, returning to 72°F at 6:55 p.m. Which statement best explains whether or not the temperature in the oven is a function of the time?

Answer 1

A. It is a function because at any given time the oven was exactly one temperature.
B. It is a function because the oven temperature was the same at different times.
C. It is not a function because at any given time the oven was exactly one temperature.
D. It is not a function because the oven temperature was the same at different times.

Answer 2

For a relation to be a function, each input value must produce, at most, one output value.

Notice how each time, the oven was exactly one temperature (i.e. at 6:55 p.m, the oven temperature was 72°F. it was not simultaneously 72 and 60 degrees, for example.