document.write( "Question 97111This question is from textbook precalculus graphs and models
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\n" ); document.write( " 3+ sqrt 5 , I know that you have to use the conjugates when the same # with the different sign in the middle, so it should then look like this
\n" ); document.write( " 6 3-sqrt5 18 +6sqrt 5
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\n" ); document.write( "\n" ); document.write( "then I think you foil the denominator, and get (3+sqrt5)(3-sqrt5), and this = to 9+3-sqrt5+3+sqrt5, and sqrt -5 and sqrt 5=-25, =-5and the middle cancels out and leaves you with 9-5=4 but the answer in the back of book is 9-3sqrt5
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\n" ); document.write( "how did they get that? thank you for your time. Stacy
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Algebra.Com's Answer #70677 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'm assuming you want to rationalize the denominator right?\r
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\n" ); document.write( "\n" ); document.write( "\"6%2F%283%2Bsqrt%285%29%29\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "\"%286%2F%283%2Bsqrt%285%29%29%29%28%283-sqrt%285%29%29%2F%283-sqrt%285%29%29%29\" Multiply the fraction by \"%283-sqrt%285%29%29%2F%283-sqrt%285%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"6%283-sqrt%285%29%29%2F%283%2Bsqrt%285%29%29%283-sqrt%285%29%29\" Combine the fractions\r
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\n" ); document.write( "\n" ); document.write( "\"6%283-sqrt%285%29%29%2F%283%2A3-3%2Asqrt%285%29%2B3sqrt%285%29-sqrt%285%29%2Asqrt%285%29%29\" Foil\r
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\n" ); document.write( "\n" ); document.write( " Combine and cancel out like terms\r
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\n" ); document.write( "\n" ); document.write( "\"6%283-sqrt%285%29%29%2F%289-5%29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"6%283-sqrt%285%29%29%2F4\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"3%283-sqrt%285%29%29%2F2\" Reduce \"6%2F4\" to \"3%2F2\" (this is probably where you got lost. You should have reduced before you distributed.)\r
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\n" ); document.write( "\n" ); document.write( "\"%289-3%2Asqrt%285%29%29%2F2\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "Check:\r
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\n" ); document.write( "\n" ); document.write( "Plug in the expression \"6%2F%283%2Bsqrt%285%29%29\" into your calculator to approximately get 1.14589803375031\r
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\n" ); document.write( "\n" ); document.write( "Now plug in \"%289-3%2Asqrt%285%29%29%2F2\" into your calculator to approximately get 1.14589803375031\r
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\n" ); document.write( "\n" ); document.write( "Since they are equivalent, (ie \"6%2F%283%2Bsqrt%285%29%29=%289-3%2Asqrt%285%29%29%2F2\") this verifies our answer
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