Pedros wrote:

what is the value of x?

1) 6x=√(3x)

2) x>0

OA :

thanks

(1) Square both sides -->

36x^2=3x -->

12x^2=x, NOTE that here we can not reduce by

x, as we don't know the value of

x. Meaning that

x can be zero and if so we can not reduce (divide) by zero -->

x(12x-1)=0 -->

x=0 OR

x=\frac{1}{12}. Two possible values for

x, not sufficient.

(2)

x>0, clearly not sufficient.

(1)+(2)

x=0 OR

x=\frac{1}{12} BUT

x>0,

x can not be zero, so

x=\frac{1}{12}. Sufficient.

Answer: C.

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