alexjordan99 wrote:
Hi all
I thought that when you took the square root of a perfect square you only needed to consider the positive answer for GMAT questions so in this case the answer would be B.
Could someone please clarify
Thank you in advance
Posted from my mobile device
When the GMAT provides the square root sign for an even root, such as a square root, fourth root, etc. then the only accepted answer is the positive root. That is:
\(\sqrt{9} = 3\), NOT +3 or -3;
\(\sqrt[4]{16} = 2\), NOT +2 or -2;
Notice that in contrast, the equation \(x^2 = 9\) has TWO solutions, +3 and -3. Because \(x^2 = 9\) means that \(x =-\sqrt{9}=-3\) or \(x=\sqrt{9}=3\).
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