Answer: and
Step-by-step explanation:
First, we are told "sum of 5 times one number, x, and 4 times a second number, y, is 75":
(1)
Then, we are told "he sum of the two numbers is 18":
(2)
At this point we have our system of equations and now we are able to find the values of and
.
So, let's begin by isolating from (2):
(3)
Substituting (3) in (1):
(4)
Finding :
(5) This is the value of
Substituting (5) in (1):
(6)
Finding :
(7)
(8) This is the value of
Answer:
Last option: It is not a function because there are two different y-values for a single x-value.
Step-by-step explanation:
It is necessary to remember that, by definition, a relation is a function if each input value (x-value) has one and only one output value (x-value) .
In this case, the following points:
You can observe that the input value 4 () has two ouput values. These are:
Therefore, since there are two different y-values for a single x-value, you can conclude that the given graph is not a function.