SOLUTION: I really need the answer to this funtion and how i came to my answer.... f(x)= x+10 find f(-4), and f(x+8)

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Question 475236: I really need the answer to this funtion and how i came to my answer....
f(x)= x+10
find f(-4), and f(x+8)
Found 3 solutions by MathLover1, jim_thompson5910, Edwin McCravy:
Answer by MathLover1(20849) About Me  (Show Source):
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Finding f(-4)

f%28x%29=x%2B10 Start with the given equation.


f%28-4%29=-4%2B10 Plug in x=-4.


f%28-4%29=6 Combine like terms.

----------------------------------------------------

Finding f(x+8)


f%28x%2B8%29=x%2B8%2B10 Replace EVERY x with x+8


f%28x%2B8%29=x%2B18 Combine like terms.

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)= x+10
find f(-4), and f(x+8) 
Here is how to find f(-4):

1. Start with 

f(x) = x + 10

2. Erase the x's and put a blank where the x's were.  Now you have

f(__) =  __ + 10

3. Put -4 in the blanks:

f(-4) =  -4 + 10

Take away the underlines:

f(-4) = -4 + 10

Combine the numbers on the right:

f(-4) = 6

That's it.  It's just a substitution problem.  You look in the
parentheses after the f and whatever is in there tells you what to
substitute for x in the right side.  Then you simplify the right
side.

-----------------------

Here is how to find f(x+8):

1. Start with 

f(x) = x + 10

2. Erase the x's and put a blank where the x's were.  Now you have

f(___) =  ___ + 10

3. Put x+8 in the blanks:

f(x+8) =  x+8 + 10

Take away the underlines:

f(x+8) = x+8 + 10

Combine the numbers on the right:

f(-4) = x + 18

That's it.  It's just a substitution problem.  You look in the
parentheses after the f.  Whatever is in there tells you what to
substitute for x in the right side.  So you substitute and simplify
the right side.

Don't try to make it hard.  Just substitute for x whatever number,
letter of expression that's in the parentheses after the f, then
simplify.  What could be easier?

Edwin