document.write( "Question 1190247: If the square of a number is added to 3 times the number,the sum is 108.Find the number.
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Algebra.Com's Answer #821853 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "The words say

\n" ); document.write( "\"3x%2Bx%5E2=108\"

\n" ); document.write( "That's a quadratic equation; get everything on one side and factor:

\n" ); document.write( "\"x%5E2%2B3x-108=0\"

\n" ); document.write( "With a negative constant term, the factorization has to be of the form (x+a)(x-b); so we need two numbers whose product is 108 and whose difference is 3 -- 12 and 9.

\n" ); document.write( "\"%28x%2B12%29%28x-9%29=0\"
\n" ); document.write( "\"x=-12\" or \"x=9\"

\n" ); document.write( "Check to see if both solutions to the equation are solutions to the original problem:
\n" ); document.write( "x=-12: 3x+x^2 = -36+144 = 108 check
\n" ); document.write( "x=9: 3x+x^2 = 27+81 = 108 check

\n" ); document.write( "ANSWERS: -12 or 9

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