document.write( "Question 304084: Give a counterexample: the square of a number added to the sum of twice the number and 8 is a prime number. \n" ); document.write( "
Algebra.Com's Answer #217846 by vleith(2983)\"\" \"About 
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Pick any even number.
\n" ); document.write( "Squaring it results in a number that has a factor of 2.
\n" ); document.write( "Doubling it and adding 8 also results in a number that has a factor of 2.
\n" ); document.write( "So the resulting sum will always have a factor of 2 as well.
\n" ); document.write( "And thus cannot be prime.\r
\n" ); document.write( "\n" ); document.write( "So pick 2 or 4 or any even number.
\n" ); document.write( "And you will have your counter example
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