If (x - 1)y = 0, what is the value of x ?

Question

If (x - 1)y = 0, what is the value of x ? 
 
(1) y > 0
(2) xy = 3

atjindal · Answer

(x-1)*y=0 , x=?

1)  y>0  , this implies x-1 must be equal to 0 => x=1
2)  xy=3 
  (x-1)*y = 0 => xy-y = 0 => 3-y = 0  => y=3 and x=1

Answer - D  , Each statement alone is sufficient.

Nikkb · Answer

(x - 1)y = 0
Find: value of x 
 (x - 1)y = 0 => either x-1=0 or y=0

(1) y > 0
As y is not equal to 0 by above equation x-1 =0 => x=1
Sufficient
(2) xy = 3 
As product of 2 numbers is not equal to 0 => neither x nor y equal to 0
so above equation => x-1 =0 => x=1
Sufficient

Answer: D

atulindia · Answer

Value of x ?
Given (x-1)y=0, or xy-y=0, or one of them or both have to be zero to make this condition true.
St 1- y>0 means y is positive real no. then x-1=0, x=1--sufficient
St2- xy=3, means y =3 and positive integer then agian x-1=0 or x=1--suffcient

D is answer

das.sushmit · Answer

Hi,

Question says if (x-1)y = 0, what is the value of x?

Let's simplify the equation given.

(x-1)y = 0 means x=1 or y=0. If we can prove that y is not equal to zero then we know that x=1.

Statement 1 - y>3. Hence, since y is not = 0, x=1. Sufficient.

Statement 2 - xy=3. y here cannot be equal to zero. For example x=1, y=3. If y=0 then xy=0. Since this is not the case, y is not equal to zero and hence, x=1. Sufficient.

Answer: D

BrentGMATPrepNow · Answer

Target question :    What is the value of x?

Given : (x - 1)y = 0  
This given information tells us that there are two possible cases:
 case a : x - 1 = 0, which means x = 1
 case b : y = 0
 NOTE: At least one of the above cases must be true

Statement 1 : y > 0   
In other words, y does NOT equal zero
This rules out case b, which means  case a must be true 
In other words,  x = 1 
Since we can answer the  target question  with certainty, statement 1 is SUFFICIENT

Statement 2 : xy = 3  
From this, we can conclude that y does NOT equal zero
This rules out case b, which means  case a must be true 
In other words,  x = 1 
Since we can answer the  target question  with certainty, statement 2 is SUFFICIENT

Answer: D

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If (x - 1)y = 0, what is the value of x ?

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