I think this is a function..
Adding a negative is same as subtraction
-5+78-32
73-32
41
(-1,9) because Y is always the second number and -3*-1=3 so 9=3+6 basically :)
Answer:
B. 
Step-by-step explanation:
Given:
(2, 4) and (2, -9)
Required:
Midpoint of the vertical line with the above endpoints
Solution:
Apply the midpoint formula, which is:

Where,
(2, 4) = (x_1, y_1)
(2, -9) = (x_2, y_2)
Plug in the values into the equation:



When you have an equation that has variables and you know the value of those variables, just plug it it. So plugging the vaules we get
Just evaluating we get 4