document.write( "Question 517039: The sum of a number and 21 times it's reciprocal is -10. Find the number? \n" ); document.write( "

Algebra.Com's Answer #344608 by mananth(16946) $\"\"$ $\"About$

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let x be the number\r
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\n" ); document.write( "\n" ); document.write( "x+21/x = -21\r
\n" ); document.write( "\n" ); document.write( "LCD = x
\n" ); document.write( "multiply by LCD
\n" ); document.write( "x^2+21=-21x\r
\n" ); document.write( "\n" ); document.write( "x^2+21x+21=0
\n" ); document.write( "Find the roots of the equation by quadratic formula
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\n" ); document.write( "a= 1 ,b= 21 c 21
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\n" ); document.write( "b^2-4ac= 441 - -84
\n" ); document.write( "b^2-4ac= 357
\n" ); document.write( " $\"sqrt%28%09357%09%29\"$ = 18.89
\n" ); document.write( " $\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"$
\n" ); document.write( " $\"x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"$
\n" ); document.write( "x1=( -21 + 18.89 )/ 2
\n" ); document.write( "x1= -1.05
\n" ); document.write( "x2=( -21 -18.89 ) / 2
\n" ); document.write( "x2= -19.947 \r
\n" ); document.write( "\n" ); document.write( "m.ananth@hotmail.ca \r
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