If x is a non-zero integer, what is the value of xy?

Question

(1) x = 2

(2)  128^x*6^{(x + y)} = 48^{(2x)}*3^{(-x)}

intheend14 · Answer

Statement 1 is clearly insufficient. 
Statement 2: You can combine all the bases with the exponent "x". They all end up cancelling out and yielding 6^y=1^x. Here, 1^x is always equal to 1, so 6^y=1 and that should be sufficient.

Answer B

navkaran · Answer

Statement 1 not sufficient since we clearly dont know value of y
Statement 2 can be simplified to reach 2^y*3^y=1, 6^y=1
This means y=0
This is enough to find xy that is 0

Answer B

kinghyts · Answer

Statement 1 is clearly insufficient, since we don't know the value of y

Statement 2: 
128^x*6^(x + y) = 48^(2x)*3^(-x)

This can be simplified as

2^8x * 2^y * 3^x*3^y = 2^8x*3^x
=> 2^y *3^y=1
Only possible if y = 0

Therefore xy = 0. Sufficient

Hence B) is the answer

anupamadw · Answer

Statmnt1) Nothing we know about Y...Insuff

Statmnt2)
2^7x * 2^(x+y) * 3^(x+y) = 3^2x*2^8x*3^(-x)
2^8x+y * 3^(x+y) = 3^x * 2^8x

so y=0 -> xy=0

Suff, IMO B

Mo2men · Answer

If x is a non-zero integer, what is the value of xy?

x could negative or positive integer. y could be any number

(1) x = 2

No info about y.

Insufficient

(2) 128^x*6^(x + y) = 48^(2x)*3^(-x)

Simplifying the equation above keeping an eye of 3 as it has x & y......... 3^(x+y) = 3^x

x+y=x............then y=0

xy=0

Sufficient

Answer: B

Kinshook · Answer

If x is a non-zero integer, what is the value of xy?

(1) x = 2 
Since y is unknown 
Not sufficient

(2)  128^x*6^{(x + y)} = 48^{(2x)}*3^{(-x)} 
2^{7x}*2^{x+y}*3^{x+y}=2^{8x}*3^{2x}*3^{-x}
2^{8x+y}*3^{x+y} = 2^{8x}*3^{x}
y=0
xy=0
Sufficient

IMO B

If x is a non-zero integer, what is the value of xy?

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