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Graphing points

Date: 4/13/96 at 21:55:3
From: Anonymous
Subject: Graphing points

I am having a hard time undestanding this subject:
f(x)=4    and   g(x)=2

First question: which is the Y axis and which is the X axis?
The actual problem is as follows:

f(x)=x-2(3)+4 ; g(x)=x-2(3)+4

I replaced the f(x) and g(x) with their appropriate numbers, yet I 
still couldn't find F or G and the extra X really confused me! I need 
some help!

Date: 9/19/96 at 18:44:10
From: Doctor Chaos
Subject: Re: Graphing points

If your typing is correct, I understand f(x) to be 2 minus 2 times 3 
plus 4.

Since f(x) is to be 4, we just substitute, as you said, and we get:

4 = x-2(3)+4

If we simplify things a bit on the right hand side of this equation, 
we should get:

4 = x-10

Since 4 is the result of some number minus 10, that number should be 
14. This is the same process you should use for g(x).

Keep in mind that mathematicians use f(x) and g(x) and so on to 
describe functions which make ME think of things like y = x-2(3)+4 
when I see f(x) = x-2(3)+4.  So I guess that means we're talking 
about the y-axis.

Hope this helps.  Try g(x) and see what you get.

-Doctor Chaos,  The Math Forum
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Associated Topics:
High School Basic Algebra

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