document.write( "Question 896212: A club can elect a member as president and another member as treasurer in 506 different ways. How many members does the club have? \n" ); document.write( "
Algebra.Com's Answer #543327 by jim_thompson5910(35256)\"\" \"About 
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Let's say we had x members total\r
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\n" ); document.write( "\n" ); document.write( "That means we have x choices for president (assuming they are all candidates). \r
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\n" ); document.write( "\n" ); document.write( "That leaves us with x-1 choices for treasurer. We cannot pick the same person to run both positions.\r
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\n" ); document.write( "\n" ); document.write( "So we have x*(x-1) ways to pick 2 people (from a pool of x people)\r
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\n" ); document.write( "\n" ); document.write( "We know that there are 506 ways to do this, so x*(x-1) = 506\r
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\n" ); document.write( "\n" ); document.write( "Solve for x\r
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\n" ); document.write( "\n" ); document.write( "x*(x-1) = 506\r
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\n" ); document.write( "\n" ); document.write( "x^2-x = 506\r
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\n" ); document.write( "\n" ); document.write( "x^2-x-506 = 0\r
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\n" ); document.write( "\n" ); document.write( "Use the quadratic formula to get the solutions x = 23 or x = -22. \r
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\n" ); document.write( "\n" ); document.write( "I show the steps in solving here.\r
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\n" ); document.write( "\n" ); document.write( "x is the number of people, so it has to be a positive whole number. That means we ignore x = -22\r
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\n" ); document.write( "\n" ); document.write( "The only practical solution is x = 23.\r
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\n" ); document.write( "\n" ); document.write( "That means the club has 23 members.\r
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\n" ); document.write( "\n" ); document.write( "Notice how\r
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\n" ); document.write( "\n" ); document.write( "x*(x-1) = 506\r
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\n" ); document.write( "\n" ); document.write( "23*(23-1) = 506\r
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\n" ); document.write( "\n" ); document.write( "23*22 = 506\r
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\n" ); document.write( "\n" ); document.write( "506 = 506\r
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\n" ); document.write( "\n" ); document.write( "So that confirms the answer.\r
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