In such questions where the square root symbol is absent from the question you always consider the positive and negative values.

exactly, that's what I thought so too. it's D.

The answer is C, in the GRE if there is not a negative symbol before the quantity you don't really consider the negative. If it's for example Positive Sqrt(25) then the answer is 5.

If you want negative 5 then it would be Negative Sqrt(5) in which the answer is negative 5.

What is the ans actually? is it C or D?

C Sir

we edited the OA in the question

OA should be D

Which is right? 5lb says its D.

But how can it be that then the result becomes 16:-28?

\(\frac{16}{g} = \frac{g}{49}\)

\(g^2 = 49*16\)

\(g = 28 \)

Hence answer C

answer is c
and i think this question is Manhattan prep quant book.

What is answer sir, you are saying C, OA saying its D, For my knowledge its should C as official guide clearly mention that square root can not be negative. Its pretty confusing. Need help from Quant expert GreenlightTestPrep

16/g=g/49

simplify

16/49 that is a positive amount

however wed DO NOT know what g is

D is the answer

There is an important difference between the equation x² = 25 and the equation x = √25

There are TWO solutions to the equation x² = 25. Here's why:
We can subtract 25 from both sides of this equation to get: x² - 25 = 0
Factor to get: (x + 5)(x - 5) = 0
So the two solutions are: x = -5 and x = 5

For the equation x = √25, we must recognize that the square root notation tells us to take the positive square root only.
So, √25 = 5
Likewise, √81= 9 and √400 = 20

So it's all about the notation.

The equation g² = (49)(16) doesn't have any square root notation.
So, g = 28 or -28

In general. if we have an equation in the form x² = k (where k > 0), then there are two solutions: x = √k and x = -√k
If we have an equation in the form x = √k, and there is one solution: x = the positive square root of k

OK , this is the most useful reply I ever seen, because based on this concept, I see at least one question in any mock test and in official guide too and Now , the idea seems clear. Thank you sir GreenlightTestPrep

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