document.write( "Question 945127: The sum of the square of a positive number and the square of 3 more than the number is 65. What is the number? \n" ); document.write( "
Algebra.Com's Answer #576327 by macston(5194)\"\" \"About 
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Let x be the positive number
\n" ); document.write( "\"x%5E2%2B%28x%2B3%29%5E2=65\"
\n" ); document.write( "\"x%5E2%2Bx%5E2%2B6x%2B9=65\"
\n" ); document.write( "\"2x%5E2%2B6x%2B9=65\" Subtract 65 from each side
\n" ); document.write( "\"2x%5E2%2B6x-56=0\"\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B6x%2B-56+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%286%29%5E2-4%2A2%2A-56=484\".
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\n" ); document.write( " Discriminant d=484 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-6%2B-sqrt%28+484+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%286%29%2Bsqrt%28+484+%29%29%2F2%5C2+=+4\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%286%29-sqrt%28+484+%29%29%2F2%5C2+=+-7\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B6x%2B-56\" can be factored:
\n" ); document.write( " \"2x%5E2%2B6x%2B-56+=+2%28x-4%29%2A%28x--7%29\"
\n" ); document.write( " Again, the answer is: 4, -7.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B6%2Ax%2B-56+%29\"

\n" ); document.write( "\n" ); document.write( "ANSWERS 4,-7 The number is restricted to positive numbers so the answer is 4.
\n" ); document.write( "CHECK:
\n" ); document.write( "\"x%5E2%2B%28x%2B3%29%5E2=65\"
\n" ); document.write( "\"4%5E2%2B%284%2B3%29%5E2=65\"
\n" ); document.write( "\"16%2B49=65\"
\n" ); document.write( "65=65
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