document.write( "Question 579097: Find two consecutive odd integers such that the square root of the larger is four less than the smaller. \n" ); document.write( "
Algebra.Com's Answer #370854 by dfrazzetto(283)\"\" \"About 
You can put this solution on YOUR website!
Intuitively, we can guess it is 7 and 9, which works, but to solve it mathematically\r
\n" ); document.write( "\n" ); document.write( "2n+1, 2n+3\r
\n" ); document.write( "\n" ); document.write( "\"sqrt%282n%2B3%29+=+2n%2B1-4\"
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\n" ); document.write( "\"sqrt%282n%2B3%29+=+2n-3\"
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\n" ); document.write( "Square both sides:
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\n" ); document.write( "2n+3 = 4n^2 -12n + 9\r
\n" ); document.write( "\n" ); document.write( "4n^2 - 14n + 6 = 0; divide by 2
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\n" ); document.write( "2n^2 - 7n + 3 = 0; factor:
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\n" ); document.write( "(2n - 1)(n - 3) = 0\r
\n" ); document.write( "\n" ); document.write( "n = 1/2 or 3\r
\n" ); document.write( "\n" ); document.write( "plugging 1/2 into original equations gives us 2 and 4 which are even, so throw that out\r
\n" ); document.write( "\n" ); document.write( "plugging 3 into original equations gives us 7 and 9, which work\r
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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-7x%2B3+=+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=%28-7%29%5E2-4%2A2%2A3=25\".
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\n" ); document.write( " Discriminant d=25 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--7%2B-sqrt%28+25+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-7%29%2Bsqrt%28+25+%29%29%2F2%5C2+=+3\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-7%29-sqrt%28+25+%29%29%2F2%5C2+=+0.5\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-7x%2B3\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-7x%2B3+=+2%28x-3%29%2A%28x-0.5%29\"
\n" ); document.write( " Again, the answer is: 3, 0.5.\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-7%2Ax%2B3+%29\"
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