Answer:
6x+20
c.
Step-by-step explanation:
If f(x)=6x+2 and you are asked to find f(x+3), then you just replace all the x's in f(x)=6x+2 with (x+3).
Doing this gives you:
f(x)=6x+2 with new input (x+3) in place of out input (x)
f(x+3)=6(x+3)+2
f(x+3)=6x+18+2
f(x+3)=6x+20
