How Do You Solve Absolute Value Inequalities with Double Variables?

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h00zah
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how do you go about solving abs value inequalities with double variables when the abs value bars are on both the variables?

eg; |x| + or - |y| =, >, <, a
 
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I know that when |x| < a it must be -a < x < a, but when |x| "is less than or equal to" a, how do you represent both rules at once?

this is not h.w, we're doing this in class and we haven't been shown how to do this and there are no examples in my text.
 
h00zah said:
but when |x| "is less than or equal to" a, how do you represent both rules at once?
You don't
You divide the problem into n regions/conditions.
In this problem it is four conditions; x and y , positive and negative.

Then the interval solutions depend on the condition/region.

Check out
http://www.purplemath.com/modules/absineq.htm
 
h00zah said:
I know that when |x| < a it must be -a < x < a, but when |x| "is less than or equal to" a, how do you represent both rules at once?
Like this: -a <= x <= a
h00zah said:
this is not h.w, we're doing this in class and we haven't been shown how to do this and there are no examples in my text.