MathRevolution wrote:

When x and y are integers, is x+y an even?

1) x^2+y^2 is an even

2) (x+1)^2+(y+1)^2 is an even

*An answer will be posted in 2 days.

X and Y are integers and we have to find if x+y is integers...

If BOTH x and y are same type of numbers that is both odd or both even , ans is YES, otherwise No..

lets test the statements-

1) x^2+y^2 is an even

clearly x and y are either both odd or both even..

ans is YES..

Suff

2) (x+1)^2+(y+1)^2 is an even

clearly x and y are either both odd or both even..

ans is YES..

Suff

D

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1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372

2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

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