must you always check the validity of an absolute value?

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Do you always have to check whether the 2 solutions you got are valid?
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by sumgb » Thu Oct 06, 2011 6:07 am
better to check the values... absolute value equations do not always have multiple solutions...

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by VivianKerr » Fri Oct 07, 2011 6:26 am
I would agree that it is better to be safe than sorry. Especially for Data Sufficiency, sometimes when you combine the statements it will "exclude" one of the possible values.
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by fcabanski » Fri Oct 07, 2011 10:35 pm
It's important because, as others stated, sometimes both solutions don't work. And it will help you catch a mistake if you made one in the math/algebra.