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How to answer these absolute value equations (1 Viewer)

x_cp3

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Critical values table if you know what i mean
 

Drongoski

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|x+2|+|3x-1|<5
|x-3|+|x+4|=x-2
thanks ^^
Not 2U Advanced questions.

For 1st one I think it's for -1 < x < 1

2nd question: no solution (no x satisfies the equation).
 
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SpiralFlex

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1. If you want to use the graphical method:





There are three cases,

For






For






For





Now you got this first part of the graph

Graph each part, now since I am lazy: http://img710.imageshack.us/i/mspaint2.png/

Now graphing

You will see the solution is:

Ask yourself where is the graph less than that line ? So finding the points of intersection and reading off the graph you will get the answer of

Did anyone get no solutions for the second question?
 
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Drongoski

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You should like a wizard and I sound like your apprentice. :)
I note: you have grown in stature mathematically - you've taken only 6 months whereas I have taken like . . . .

Confession

I got Q2 wrong at first myself whereas you got it right 1st time.
 
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Would be much easier to graph |x+2| and |3x-1| then do the addition of ordinates thing, but that's 4U...
 

Drongoski

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Oh it's you Pierre. For a moment I took it seriously.
 

mirakon

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lol drongoski, ol' matty's gonna get banned within 48 hours.
 

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