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Bunuel
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xy+ x= odd

Two possibilities:
(1) even + odd = odd
(2) odd + even= odd
In this case, x can not be even as it will make xy also even .
Therefore, (1) possibility present => y must be even.

Answer: B
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Given that xy + x is odd, which means x(y+1) is odd.
Product of two nos. will be odd only if both the nos. are odd.
Hence x is odd, y+1 is also odd.
y+1 is odd means y is even. Answer will be B.
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Option B

x & y are Positive Integers. Odd: O, Even: E & Fraction: F.
xy + x = O
i.e., x = O & y = E
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Bunuel
x and y are positive integers. If xy + x is odd, then which of the following must be even?

A. x
B. y
C. x + y
D. xy − x
E. x^2 − y

We are given that x and y are positive integers and that xy + x is odd, or x(y + 1) is odd, which means that x is odd and y is even. Thus, y MUST be even.

Answer: B
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Hello from the GMAT Club BumpBot!

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