SOLUTION: Please help me solve this problem. Given f(x)= 2x + 4, find f(a-4). I would appreciate help with this problem. I am a little confused. Thank you for your help.

Algebra ->  Functions -> SOLUTION: Please help me solve this problem. Given f(x)= 2x + 4, find f(a-4). I would appreciate help with this problem. I am a little confused. Thank you for your help.      Log On


   

Question 120736: Please help me solve this problem.
Given f(x)= 2x + 4, find f(a-4). I would appreciate help with this problem. I am a little confused. Thank you for your help.
Found 2 solutions by jim_thompson5910, rapaljer:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=+2x+%2B+4 Start with the given function


f%28a-4%29=+2%28a-4%29%2B+4 Plug in x=a-4


f%28a-4%29=+2a-8%2B+4 Distribute


f%28a-4%29=+2a-4 Combine like terms

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
If f(x)= 2x + 4, then f(a-4) means to substitute a-4 in place of the x.
f(a-4) = 2(a-4) + 4
f(a-4) = 2a -8 +4
f(a-4) = 2a-4

See my explanation on my website by clicking on my tutor name "rapaljer" anywhere on algebra.com. Click on the first link which is "Basic and Intermediate Algebra", then go to Basic Algebra, Chapter 4, and look for Section 4.09 Functional Notation.

R^2