document.write( "Question 530882: A number exceeds four times its reciprocal by 3. Find the number. \n" ); document.write( "
Algebra.Com's Answer #350239 by oberobic(2304)\"\" \"About 
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x = a number
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\n" ); document.write( "It exceeds it's reciprocal by 3
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\n" ); document.write( "x = 1/x + 3
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\n" ); document.write( "multiply both sides by x to eliminate the fraction
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\n" ); document.write( "x^2 = 1 + 3x
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\n" ); document.write( "x^2 -3x -1 = 0
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\n" ); document.write( "This will not factor, but it can be solved by the quadratic equation.
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-3x%2B-1+=+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=%28-3%29%5E2-4%2A1%2A-1=13\".
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\n" ); document.write( " Discriminant d=13 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--3%2B-sqrt%28+13+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-3%29%2Bsqrt%28+13+%29%29%2F2%5C1+=+3.30277563773199\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-3%29-sqrt%28+13+%29%29%2F2%5C1+=+-0.302775637731995\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-3x%2B-1\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-3x%2B-1+=+1%28x-3.30277563773199%29%2A%28x--0.302775637731995%29\"
\n" ); document.write( " Again, the answer is: 3.30277563773199, -0.302775637731995.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-3%2Ax%2B-1+%29\"
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