document.write( "Question 132598: If a certain positive number is added to 4 times the reciprocal of 10 less than the number, the result is 5. What is one of the numbers?
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document.write( "a. -6
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document.write( "b. -10
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document.write( "c. -9
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document.write( "d. 4 \n" );
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Algebra.Com's Answer #96906 by ptaylor(2198)![]() ![]() You can put this solution on YOUR website! Let x=the certain positive number\r \n" ); document.write( "\n" ); document.write( "10 less than this number is x-10 \n" ); document.write( "The reciprocal of 10 less than the number is 1/(x-10) \n" ); document.write( "4 times the reciprocal is 4/(x-10)\r \n" ); document.write( "\n" ); document.write( "Now we are told the following:\r \n" ); document.write( "\n" ); document.write( "x + 4/(x-10)=5 multiply each term by (x-10) \n" ); document.write( "x(x-10)+4=5(x-10) get rid of parens\r \n" ); document.write( "\n" ); document.write( "x^2-10x+4=5x-50 subtract 5x from and add 50 to both sides\r \n" ); document.write( "\n" ); document.write( "x^2-10x-5x+4+50=5x-5x-50+50 collect like terms\r \n" ); document.write( "\n" ); document.write( "x^2-15x+54=0 quadratic in standard form and it can be factored:\r \n" ); document.write( "\n" ); document.write( "(x-6)(x-9)=0\r \n" ); document.write( "\n" ); document.write( "x-6=0 \n" ); document.write( "x=6-----------------------possible solution \n" ); document.write( "x-9=0 \n" ); document.write( "x=9---------------------------another possible solution\r \n" ); document.write( "\n" ); document.write( "CK \n" ); document.write( "for x=6 \n" ); document.write( "6+4/(6-10)=5 \n" ); document.write( "6-1=5 \n" ); document.write( "5=5-----------------------------x=6 is a solution \n" ); document.write( "for x=9 \n" ); document.write( "6+4/(9-10)=5 \n" ); document.write( "6-4=5 \n" ); document.write( "2=5------------------------------x=9 is not a solution\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor \n" ); document.write( " |