SOLUTION: How do you use absolute value signs when simplifying radicals?

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Question 1019087: How do you use absolute value signs when simplifying radicals?
Found 2 solutions by fractalier, Theo:
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
You know that when you take the square root of a number, you get a positive value and a negative value...
sqrt%2825%29+=+5+or+-5
If all that concerns you is the positive value, then you can state it so by placing absolute value signs on it...sometimes we do that with variables, like this...
sqrt%28x%5E2%29+=+abs%28x%29 or sqrt%28%28y+-+7%29%5E2%29+=+abs%28y-7%29
Does that help or do you have further questions?

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
i believe this may be the rule that you are looking for.

$$$

it comes from this tutorial (about 2/3 to 3/4 of the way down in the tutorial).

http://www.wtamu.edu/academic/anns/mps/math/mathlab/int_algebra/int_alg_tut37_radical.htm


the basic rule is:

if your equation is x^2 = a, then take the square root of both sides of the equation to get x = plus or minus square root of (a).

if your equation is square root of (x^2) = b, then your solution is that x = absolute value of (b).

they seem to be sticklers for this and it's a real pain to remember, but after a few times, you'll get the hang of it.

fortunately, most of the time, you are solving the first form, where you get something like x^2 = a, and you take the square root of both sides of the equation to get x = plus or minus square root of (a).