Question

Please help!!! 50 points!!

1) Which of the following sets represents the domain of the function shown?
((2,7),(15,13),(21,-4),(24,18))
A) (-4, 2, 7, 13, 15, 18, 21, 24)
B) ((7,2),(13,15),(-4,21),(18,24)
C) (2,15,21,24)
D) (-4,7,13,18)

2) The table shows the outputs y for different inputs x:
Input(x): 3,7,11,15
Output(y): 4,7,8,10

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

Answer 1

#1,

The domain is all of the x-values.

The x-values of the set are: 2, 15, 21, 24

Your answer is C.


#2,

Part A)
Yes, the data in the table represents a function because each x-value has exactly one y-value. Also, the function passes the vertical line test.

Part B)
f(x) = 5x - 21
f(11) = 5(11) - 21
f(11) = 55 - 21
f(11) = 34

The table has a y-value of 8, when x = 11.

Therefore, f(x) = 5x - 21 has a greater value than the table when x = 11

Part C)
f(x) = 99
f(x) = 5x - 21

5x - 21 = 99
5x = 120
x = 24

The value of x is 24.