document.write( "Question 519727: the sum of an integer and its square is 72. What's the integer? \n" ); document.write( "

Algebra.Com's Answer #345743 by oberobic(2304) $\"\"$ $\"About$

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x +x^2 = 72
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\n" ); document.write( "x^2 +x -72 = 0
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\n" ); document.write( "factor
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\n" ); document.write( "(x+9)(x-8) = 0
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\n" ); document.write( "x = -9 or 8
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\n" ); document.write( "check both values.
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\n" ); document.write( "-9^2 = 81
\n" ); document.write( "81+(-9) = 72
\n" ); document.write( "correct
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\n" ); document.write( "8^2 = 64
\n" ); document.write( "64 + 8 = 72
\n" ); document.write( "correct
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\n" ); document.write( "The integer is either -9 or 8.
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\n" ); document.write( "Done. \n" ); document.write( "

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