GREPlease wrote:

Surely quantity B could be -4, therefore making D the correct answer?

Many students will answer this question incorrectly because they believe that the square root of a number can be negative.

For example, some students believe that √36 = 6 or -6

However, this is not the case. The square root

notation (√) tells us to identify the POSITIVE value that, when squared, equals 36

Cheers,

Brent

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Brent Hanneson – Creator of greenlighttestprep.com

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