Hi Rose,

$f(a) = a + 5$ and look at my response to brian concerning a similar question. In your question the letter $a$ is the input variable where in Brian's question the input variable was $x,$ and hence in your question the output is $f(a).$ Thus your function rule be explained by "add 5 to the input".

Now construct a table similar to the table in my response to Brian and fill it in.

Write back if you need more assistance,
Harley