document.write( "Question 985344: Find a square number which, being increased or diminished by 5, gives a square number.\r
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Algebra.Com's Answer #606189 by Edwin McCravy(20055)\"\" \"About 
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document.write( "The only two positive square numbers that differ by 5 are 4 and 9.  [9 and 16\r\n" );
document.write( "differ by 7, 16 and 25 differ by 9, and the difference gets larger and larger.\r\n" );
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document.write( "So 4 is the ONLY square number which, being increased by 5, gives a square\r\n" );
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document.write( "However this problem also requres that when it is diminished by 5, it also gives\r\n" );
document.write( "a square number.  \r\n" );
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document.write( "When we diminish 4 by 5 we get -1.\r\n" );
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document.write( "Is -1 a square number?  Well yes, in a sense, because i² = -1.\r\n" );
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document.write( "So the only possible answer could be 4 which when increased by 5 gives square\r\n" );
document.write( "number 9 and when diminished by 5, gives -1, which is the square of the\r\n" );
document.write( "imaginary number i.\r\n" );
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document.write( "That's just asking the same thing in another way.\r\n" );
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document.write( "5 is the only number when added to the square number 4 or subtracted from the\r\n" );
document.write( "square number 4 to give either the square number 9, which is 3² or the square\r\n" );
document.write( "number -1, or i², which is a square number if we consider the square of an\r\n" );
document.write( "imaginary number as a square number.  .  \r\n" );
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document.write( "Edwin
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