Finding x Values for x + 4 > 2/|x+3|: Algebraic Solution

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To solve the inequality x + 4 > 2/|x + 3|, it is crucial to keep the absolute value in the equation rather than removing it prematurely. The correct approach involves maintaining the absolute value and rewriting the inequality as (x + 4)|x + 3| > 2. A sign chart can be useful for identifying critical points where the expression equals zero or is undefined, specifically at x = -5 and x = -3. Testing intervals around these points reveals that the valid solution is x > -2. This method ensures an accurate algebraic solution without relying on graphical representation.
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find the values of x for which

x + 4 > \dfrac{2}{|x+3|}

as the | x + 3 | is positive I thought it would be okay to just bring it over so:

(x+4)(x+3) &gt; 2 solving this, I get x > -2 and x < - 5

however drawing a sketch of the original question shows that the only value needed is x > - 2

my question is why doesn't my method work, and is there a way to do this algebraically without any graph drawing?
 
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phospho said:
as the | x + 3 | is positive I thought it would be okay to just bring it over so:

(x+4)(x+3) &gt; 2 solving this, I get x > -2 and x < - 5
It may be okay to "just bring it over," but that does not mean you can drop the absolute value symbol. You still need them:
(x+4)|x+3| &gt; 2

phospho said:
my question is why doesn't my method work, and is there a way to do this algebraically without any graph drawing?
Make a sign chart. Find values that make the original inequality 0 or undefined, and plot them on a number line:
Code:
<--------+--------+--------+-------->
        -5       -3       -2
Test a value in each interval to see if the inequality holds.
 
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