document.write( "Question 184875: The sum of the reciprocals of two even numbers equals 11/60.
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document.write( "Write an equation and find the two numbers.
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document.write( "This really stumped me....please help!!!!! \n" );
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Algebra.Com's Answer #138735 by solver91311(24713) You can put this solution on YOUR website! \r \n" ); document.write( "\n" ); document.write( "I don't blame you a bit for being stumped on this one. I had to chew on it all afternoon. But I did come up with two solutions.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now if you add the two fractions containing the variables:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "From which you could derive two equations by equating the numerators and equating the denominators. But there is a problem. Setting the numerators equal to each other gives you:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And there are no two even numbers that will satisfy this equation. This is where I was stumped for a while until it occured to me to make a little change to the equation, thus:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now we can say:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Rearranging the first equation:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And substituting in the second equation:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And this quadratic factors rather tidily:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Therefore:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "or\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And going back to:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "We can see that y is 12 when x is 10, or vice versa, so the two numbers are 10 and 12.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Check:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Done, right? Not so fast, Sparky. Like the guy on TV selling Ginzu knives says, \"But wait...there's more!\"\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "After obtaining that result, it occurred to me that if multiplying \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So I tried \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "which has irrational roots, and is therefore not a solution (verification of this left as an exercise for the student)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Then I tried So I tried \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Which factors to:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Giving us 6 and 60 as the two numbers.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Check:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I actually tried about a hundred different values of k but only found the two I showed you that worked, so I'm pretty certain that these are the only two solutions to the problem as stated.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Thanks. I had fun with this one.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "John \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |