SOLUTION: Solve the absolute value inequality. Write the solution set using interval notation |b + 4| - 7 > 11

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Question 447471: Solve the absolute value inequality. Write the solution set using interval notation
|b + 4| - 7 > 11

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
Exponents/447471 (2011-05-10 08:40:47): Solve the absolute value inequality. Write the solution set using interval notation
|b + 4| - 7 > 11
Get the absolute value term by itself by adding 7 to both sides:

    |b + 4| > 18

There are four rules for removing absolute value bars in
absolute value inequalities:

If A is positive:

1.  |EXPRESSION| < A becomes 

-A < EXPRESSION < A

2.  |EXPRESSION| ≦ A becomes 

-A ≦ EXPRESSION ≦ A

3.  |EXPRESSION| > A becomes

EXPRESSION < -A  OR EXPRESSION > A 

4.  |EXPRESSION| ≧ A becomes

EXPRESSION ≦ -A  OR EXPRESSION ≧ A

-----------------------------------------

    |b + 4| > 18

is rule 3 above where EXPRESSION = b + 4 and A = 4

    |b + 4| > 18 becomes

b + 4 < -18  OR  b + 4 > 18

Solve each for b:

    b < -22 OR  b > 14  

Draw the graph on a number line:

<==============o-----------------------o===============>
             -22                      14 

Then the interval notation for this is an abbreviation 
for this graph

                   (-∞,-22) U (14,∞)

Edwin