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johnycute
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tennis1ball
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Yes, got the point of tennis_ball
It should be E

In fact, x^2 + y^2 is not divisible by 5 when x = 4.5 and y = 3.5, whereas these values satisfy other conditions.
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hobbit
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tennis ball is right...

x=2 y=1 satisfy (1) and (2) and x^2+y2 is divisible by 5.
however -
x=4.5 y=3.5 satisfy (1) and (2) and x^2+y^2 is not even an integer... not to say that it is not divisible by 5.

nothing said in the question that x and y should be integers.

hence E.
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FN
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this is a very simple problem...

I get E..

X^2 + y^2=(x+y)(x-y)

1) ok so we are told (x-y)=5m+1; but we dont know anything about (x+Y)..insuff

2) same thing

now C) lets look

(x-y)(x+y), we have remainders 3 and 1...pick a number

x-y=6; x+y=8; 8*6=42/5 remainder is 2

pick another number x-y =11; x+y=8; 8*11=88/5 remainder is 3...

Insuff...E it is..
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Thanks everyone, yes, I assumed x and y are integers
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chile
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Just for the record

x^2+y^2 is not equal (x-y)(x+y)

x^2-y^2 = (x-y)(x+y)



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