document.write( "Question 73069: Twice the square of a positive integer is 35 more than 9 times that integer. What is the integer?
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Algebra.Com's Answer #52329 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Remember \"is\" means equals.
\n" ); document.write( "\"2%28x%29%5E2=35%2B9x\"Here's the translated version
\n" ); document.write( "\"2x%5E2-9x-35=0\"Solve for x by getting everything to one side
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-9x%2B-35+=+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=%28-9%29%5E2-4%2A2%2A-35=361\".
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\n" ); document.write( " Discriminant d=361 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--9%2B-sqrt%28+361+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-9%29%2Bsqrt%28+361+%29%29%2F2%5C2+=+7\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-9%29-sqrt%28+361+%29%29%2F2%5C2+=+-2.5\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-9x%2B-35\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-9x%2B-35+=+2%28x-7%29%2A%28x--2.5%29\"
\n" ); document.write( " Again, the answer is: 7, -2.5.\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%2B-9%2Ax%2B-35+%29\"

\n" ); document.write( "\n" ); document.write( "Since the problem states the integer is positive, the only answer is 7. So 7 is the integer.
\n" ); document.write( "Check:
\n" ); document.write( "\"2%287%29%5E2=35%2B9%287%29\"
\n" ); document.write( "\"98=98\"Works
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