Is x = y?

Question

Is x = y?

(1)  |x-2|= 5 .

(2)  y^2-4y-21=0 .

prachi18oct · Answer

X = -3 or 7
Y = 7 or -3 
Not necessarily equal

prachi18oct · Answer

A and B are insufficient
A = -3 or 7
Y = 7 or -3 
Not necessarily equal still as x can be 7 and y be -3
E

kumarparitosh123 · Answer

Both together not sufficient.
X=-3 or 7 and Y =-3 or7.
So E.

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Bunuel · Answer

Is x = y?

(1)  |x-2|= 5 . Clearly insufficient as no info about  y . But from this statement we know that either  x=7  or  x=-3 .

(2)  y^2-4y-21=0 . Clearly insufficient as no info about  x . But from this statement we know that either  y=7  or  y=-3 .

(1)+(2) Now, it's possible that  both   x  and  y  equal to -3 (or 7) and in this case the answer would be YES:  x=y  BUT it's also possible  x  to be -3 and  y  to be 7 (or vise-versa) and in this case answer would be NO:  x
eq{y} . Two different answers to the question, hence not sufficient.

Answer: E.

ScottTargetTestPrep · Answer

Statement One Alone:

|x - 2| = 5

Let’s test for each case: when (x - 2) is positive and when it is negative:

When (x - 2) is positive:

x - 2 = 5

x = 7

When (x - 2) is negative:

-(x - 2) = 5

-x + 2 = 5

-x = 3

x = -3

Since we know nothing about y, statement one alone is not sufficient to answer the question.

Statement Two Alone:

y^2 - 4y - 21 = 0

(y - 7)(y + 3) = 0

y = 7 or y = -3

Since we know nothing about x, statement two alone is not sufficient to answer the question.

Statements One and Two Together:

Using statements one and two, we know that x = 7 or -3 and y = 7 or -3, but we still cannot conclude whether x = y. If x = 7 and y = 7, then x = y, but if x = -3 and y = 7, then x ≠ y. The two statements together are still not sufficient to answer the question. .

Answer: E

Is x = y?

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