Quant Problem with Squares and Square Roots

GRE Quant Problem Solving
1

\sqrt{y^2} = 8

Quantity A = 3^{2y}
Quantity B = 3^{-2y}

Should I ignore the negative root of y here? if or if not, why?

2

Please check this thread: I can't figure out why the square root of this algebraic equation won't have a positive and a negative root

Hope you find it useful

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3

In this case you should not ignore it
The rule by ETS is that there can’t be a negative value under the root
For y = 8, the value under the root is 64
For y = -8, the value under the root is also 64

So, we are not violating any ETS rules by having y = -8

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