document.write( "Question 796205: A two digit number is 18 less than the sum of the squares of its digits. How many such numbers are there? \n" ); document.write( "
Algebra.Com's Answer #481468 by MathTherapy(10555)\"\" \"About 
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\n" ); document.write( "A two digit number is 18 less than the sum of the squares of its digits. How many such numbers are there?\r
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\n" ); document.write( "\n" ); document.write( "Let tens and units digits be T and U, respectively
\n" ); document.write( "Then: \"10T+%2B+U+=+T%5E2+%2B+U%5E2+-+18\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+U%5E2+-+U+-+18+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "Since the number is 18 less than the sum of the squares of its digits, then its units digit is greater than its tens digit, or U > T.\r
\n" ); document.write( "\n" ); document.write( "Therefore, with 9 being the largest digit, we:\r
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\n" ); document.write( "\n" ); document.write( "Let U = 9
\n" ); document.write( "\"T%5E2+-+10T+%2B+U%5E2+-+U+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+81+-+9+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+54+=+0\" ----- T is NOT an INTEGER\r
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\n" ); document.write( "\n" ); document.write( "Let U = 8
\n" ); document.write( "\"T%5E2+-+10T+%2B+U%5E2+-+U+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+64+-+8+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+40+=+0\" ----- T is NOT an INTEGER\r
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\n" ); document.write( "\n" ); document.write( "Let U = 7
\n" ); document.write( "\"T%5E2+-+10T+%2B+U%5E2+-+U+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+49+-+7+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+24+=+0\"
\n" ); document.write( "T, or tens digit = 6 or 4\r
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\n" ); document.write( "\n" ); document.write( "This means that the number could be \"highlight_green%2867%29\", or \"highlight_green%2847%29\"\r
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\n" ); document.write( "\n" ); document.write( "Let U = 6
\n" ); document.write( "\"T%5E2+-+10T+%2B+U%5E2+-+U+%96+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+36+-+6+-+18+=+0\"
\n" ); document.write( "\"T%5E2+-+10T+%2B+12+=+0\" ----- T is NOT an INTEGER\r
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\n" ); document.write( "\n" ); document.write( "No need to go any further since T ≠ U, and U > T \r
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\n" ); document.write( "\n" ); document.write( "You can do the check!! \r
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\n" ); document.write( "\n" ); document.write( "Send comments, “thank-yous,” and inquiries to “D” at MathMadEzy@aol.com. Further help is available, online or in-person, for a fee, obviously. \r
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