Question

The table below shows the fourth powers of different numbers: Number (x) 1 −1 2 −2 Fourth power of the number (y) 1 1 16 16 Part A: Does the table represent y as a function of x? Justify your answer. (5 points) Part B: The total cost f(x), in dollars, for renting a truck for x hours is shown below: f(x) = 17x + 50 What is the value of f(30) and what does f(30) represent? (5 points)

Answer 1

Part A: yes it is a function because every input value (x) produces only one output value (y).
Note: It is still a function if different x values produce the same y value, in this case, x=1 and x=-1 produce the same y value 1, but it is NOT a function if y=1 and y=-1 have the same x value x=1.

Part B: when x=30: f(30)=17*30+50=560
if means that the cost of renting the truck for 30 hours is 560 dollars.