document.write( "Question 195531: ( sqrt 5 - sqrt7)^2\r
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\n" ); document.write( "\n" ); document.write( "answer:12 - 2 sqrt 35\r
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\n" ); document.write( "\n" ); document.write( "ok so i tried the foil method and i got sqrt 5 sqrt7 as my answer can anyone tell me how my book got 12-2 sqrt 35 as an answer
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Algebra.Com's Answer #146646 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%285%29-sqrt%287%29%29%5E2\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%285%29-sqrt%287%29%29%28sqrt%285%29-sqrt%287%29%29\" Expand. Remember something like \"x%5E2=x%2Ax\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's FOIL the expression.\r
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\n" ); document.write( "\n" ); document.write( "Remember, when you FOIL an expression, you follow this procedure:\r
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\n" ); document.write( "\n" ); document.write( "\"%28highlight%28sqrt%285%29%29-sqrt%287%29%29%28highlight%28sqrt%285%29%29-sqrt%287%29%29\" Multiply the First terms:\"%28sqrt%285%29%29%2A%28sqrt%285%29%29=sqrt%285%2A5%29=sqrt%2825%29=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28highlight%28sqrt%285%29%29-sqrt%287%29%29%28sqrt%285%29%2Bhighlight%28-sqrt%287%29%29%29\" Multiply the Outer terms:\"%28sqrt%285%29%29%2A%28-sqrt%287%29%29=-sqrt%285%2A7%29=-sqrt%2835%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%285%29%2Bhighlight%28-sqrt%287%29%29%29%28highlight%28sqrt%285%29%29-sqrt%287%29%29\" Multiply the Inner terms:\"%28-sqrt%287%29%29%2A%28sqrt%285%29%29=-sqrt%287%2A5%29=-sqrt%2835%29\".\r
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\n" ); document.write( "\n" ); document.write( " Multiply the Last terms:\"%28-sqrt%287%29%29%2A%28-sqrt%287%29%29=sqrt%287%2A7%29=sqrt%2849%29=7\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the terms: \"5\", \"-sqrt%2835%29\", \"-sqrt%2835%29\", and \"7\" \r
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\n" ); document.write( "\n" ); document.write( "\"5-sqrt%2835%29-sqrt%2835%29%2B7\" Now add every term listed above to make a single expression.\r
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\n" ); document.write( "\n" ); document.write( "\"12-2%2Asqrt%2835%29\" Now combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So \"%28sqrt%285%29-sqrt%287%29%29%5E2\" FOILs to \"12-2%2Asqrt%2835%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"%28sqrt%285%29-sqrt%287%29%29%5E2=12-2%2Asqrt%2835%29\".
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