Let f(x) = 3x + 2

Question

Find f(a) and f(2a).

I'm confused, can someone help me?

Answer 1

Just substitute in a desired value.

f(x) = 3x+2
f(a) = 3a+2
f(2a) = 3(2a)+2 = 6a+2
f(4) = 3(4)+2 = 14
and so on