Question

The table shows the outputs y for different inputs x:

Input
(x) 3 7 11 15
Output
(y) 4 6 8 10


Part A: Do the data in this table represent a function? Justify your answer. (3 points)
Part B: Compare the data in the table with the relation f(x) = 5x – 21. Which relation has a greater value when x = 11? (2 points)
Part C: Using the relation in Part B, what is the value of x if f(x) = 99? (5 points)

Answer 1

Hello there.

The table shows the outputs y for different inputs x:


Input
(x) 3 7 11 15
Output
(y) 4 6 8 10


Part A: Do the data in this table represent a function? Justify your answer. (3 points)

ANswer: True/Yes

Answer 2

A: Yes, it's a function. No input value yields more than one output.


B: If f(x) = 5x - 21, then
f(11) = 5 (11) - 21 = 55 - 21 = 34

This relation has a greater value when x=11 than the one in the table,
which lists a value of 8 when x=11.


C: f(x) =
5x - 21 = 99
5x = 120 [adding 21 to each side]
x = 24 [dividing each side by 5]