document.write( "Question 955037: The sum of the squares of the digits of a certain two digit positive integer is 20. The integer is seven times the sum of its digits. Find the integer. \n" ); document.write( "
Algebra.Com's Answer #583343 by stanbon(75887)\"\" \"About 
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The sum of the squares of the digits of a certain two digit positive integer is 20. The integer is seven times the sum of its digits. Find the integer.
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\n" ); document.write( "Let the number be 10t+u
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\n" ); document.write( "Equation:
\n" ); document.write( "t^2 + u^2 = 20
\n" ); document.write( "10t+u = 7(t+u)
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\n" ); document.write( "Simplify::
\n" ); document.write( "t^2 + u^2 = 20
\n" ); document.write( "t = 2u
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\n" ); document.write( "Substitute and solve for \"u\":
\n" ); document.write( "4u^2 + u^2 = 20
\n" ); document.write( "5u^2 = 20
\n" ); document.write( "u = 2 or u = -2
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\n" ); document.write( "If u = 2, t = 4 giving you 10t+u = 42
\n" ); document.write( "if u = -2, t = -4 giving you 10t+u = -42
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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