Answer:
A function can be any set of points where one input is equal to one output. You cannot have two X values with the same Y value, for example.
<u>I believe the answer is neither</u> because in both sets you can see they have different Y values for the X values 2 and 9.
 
        
             
        
        
        
Answer:

Step-by-step explanation:
You have to solve for the x intercept on the equation 

That is the x intercept for that equation.
Then solve for the y intercept on the equation

That is the x intercept for that equation.
Use that to find slope for point slope form

1 is the slope
and slope makes B the y intercept so the equation is

 
        
             
        
        
        
1/2 a bunch because 8 divided by 4 = 1/2 :)