SOLUTION: If f(x)= 4x-3 then find f(-1). I really do not understand the whole function notation. Any help that can be given or any words to go by would be very much appreciated. Thanks.

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Question 101240: If f(x)= 4x-3 then find f(-1).
I really do not understand the whole function notation. Any help that can be given or any words to go by would be very much appreciated. Thanks.
Found 2 solutions by bucky, doukungfoo:
Answer by bucky(2189) (Show Source):
You can put this solution on YOUR website!
Given:
.
f(x) = 4x - 3
.
The problem asks you to find f(-1).
.
All that this is telling you to do is to evaluate f(x) when x equals -1. So, just go to the
given f(x) and substitute -1 for every x.
.
Starting with:
.
f(x) = 4x - 3
.
replacing every x by -1 results in:
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f(-1) = 4*(-1) - 3
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and since 4 times (-1) equals -4 the equation becomes:
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f(-1) = -4 - 3
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And on the right side the -4 and the -3 combine to -7. Therefore, the equation is finally
reduced to:
.
f(-1) = -7
.
And this is the answer you were asked to find.
.
Hope this helps you to understand how to do problems such as these by just substituting
for x the value given in the parentheses and then combining the terms as much as possible
to reduce the answer.

Answer by doukungfoo(195) (Show Source):
You can put this solution on YOUR website!
If f(x)= 4x-3 then find f(-1).
This just means replace the x with -1 and perform the operations
so
f(-1)= 4(-1)-3
f(-1)= -4 - 3
f(-1)= -7
thats it

The term f(x) is what denotes a function and is read "f of x"
The 4x-3 shows what operations you need to
perform when given and input number.
-1 is the given input number.