SOLUTION: If f(x)=1-3x,find f(-5).

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Question 92497: If f(x)=1-3x,find f(-5).
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
All you have to do is to start with the equation you were given, replace every x with -5,
and do the calculations that result. Here we go:
.
Start with f%28x%29+=+1+-+3x
.
Replace all the x's with -5:
.
f%28-5%29+=+1+-+3%28-5%29
.
do the calculations:
.
+f%28-5%29+=+1+-+%28-15%29
.
remove the parentheses on the right side. Because the parentheses are preceded by a minus
sign, when you remove the parentheses you change the sign of the term inside. The equation
then becomes:
.
f%28-5%29=+1+%2B+15+=+16
.
So the answer you are looking for is:
.
f%28-5%29+=+16
.
Hope this helps you to see how to do problems like these.