Not sure how the answers were achieved in this graph

[hyde2042]

1. The problem statement, all variables and given/known data
http://i.imgur.com/vqyXW.png




2. Relevant equations



3. The attempt at a solution

I got the DOmain and Range of the graph, but then it says to do the same for the functions a-d. If you graph them then they are all straight lines so there's really only a domain.

But when I checked at the back of the book, the answers came to be

A)0
B)-1
C)0
D)-2

I'm sure I'm missing something. Any help is appreciated. Thank you.

[dynamicsolo]

You are misunderstanding that part of the problem. They are just asking you to use the graph to read off the values of the function f(x) at each of the indicated values of x .

[hyde2042]

Ah, I see. THank you very much.