If x is an integer, is

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Source: — Data Sufficiency |

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by shahdevine » Sat Aug 01, 2009 2:20 pm
statement 1)

x is odd. look at second term, (x+5). we know odd +odd = even and anything times even is even. sufficient.

statement 2)

each prime factor of x^2 means that each prime factor is odd. the fact that its greater than 7, means that its not 2, which is the only prime that is not odd. look at second term, (x+5). we know odd+odd=even and anything times even is even. sufficient.

blue skies,

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by alexdallas » Sat Aug 01, 2009 2:25 pm
i dont understand the 2nd part:

"statement 2)

each prime factor of x^2 means that each prime factor is odd. the fact that its greater than 7, means that its not 2, which is the only prime that is not odd. look at second term, (x+5). we know odd+odd=even and anything times even is even. sufficient."

can someone explain this in a bit more detail?

thank you