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Equation with Absolute Value

Date: 3/25/96 at 22:47:57
From: Bernard Brill
Subject: HELP!

I am an 8th grade student who is taking Algebra 2. I have problems 
solving equations with absolute value and graphing on a number line.

|2n-6|> 5

My teacher said I have to factor out the 2, but I am really 
confused. Please help!

Date: 3/28/96 at 23:14:28
From: Doctor Steven
Subject: Re: HELP!

Here's how you solve inequalities with absolute values in them:

Take the inequality |3x - 9| > 4.

Step 1) Set it up like this:
        -4 > 3x - 9 or 4 < 3x -  9.

Step 2) Add 9 to both sides of both inequalities to get:

        5 > 3x  or 13 < 3x

Step 3) 5/3 > x or 13/3 < x  

Step 4) Put in familiar form to get:

        x < 5/3  or  x > 13/3.

Now all you have to do is graph the solution on the number line.

Hope this helps.

-Doctor Steven,  The Math Forum

Associated Topics:
Middle School Algebra

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