document.write( "Question 190672This question is from textbook
\n" ); document.write( ": Using FOIL, multiply the expression (3x+2)(3x-2) Show that a particular factoring formula can be used to get the same answer. Thanks so much! I'm lost again! \n" ); document.write( "
Algebra.Com's Answer #143147 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"%283x%2B2%29%283x-2%29\" Start with the given expression.\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%283x%29%2B2%29%28highlight%283x%29-2%29\" Multiply the First terms:\"%283%2Ax%29%2A%283%2Ax%29=9%2Ax%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28highlight%283x%29%2B2%29%283x%2Bhighlight%28-2%29%29\" Multiply the Outer terms:\"%283%2Ax%29%2A%28-2%29=-6%2Ax\".\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2Bhighlight%282%29%29%28highlight%283x%29-2%29\" Multiply the Inner terms:\"%282%29%2A%283%2Ax%29=6%2Ax\".\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2Bhighlight%282%29%29%283x%2Bhighlight%28-2%29%29\" Multiply the Last terms:\"%282%29%2A%28-2%29=-4\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the terms: \"9%2Ax%5E2\", \"-6%2Ax\", \"6%2Ax\", \"-4\" \r
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\n" ); document.write( "\n" ); document.write( "\"9%2Ax%5E2-6%2Ax%2B6%2Ax-4\" Now add every term listed above to make a single expression.\r
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\n" ); document.write( "\n" ); document.write( "\"9%2Ax%5E2-4\" Now combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So \"%283x%2B2%29%283x-2%29\" FOILs to \"9%2Ax%5E2-4\".\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"%283x%2B2%29%283x-2%29=9x%5E2-4\".\r
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\n" ); document.write( "\n" ); document.write( "Now, let's factor the answer to check our work:\r
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\n" ); document.write( "\n" ); document.write( "\"9x%5E2-4\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%29%5E2-4\" Rewrite \"9x%5E2\" as \"%283x%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%29%5E2-%282%29%5E2\" Rewrite \"4\" as \"%282%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have a difference of squares \"A%5E2-B%5E2\" where in this case \"A=3x\" and \"B=2\".\r
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\n" ); document.write( "\n" ); document.write( "So let's use the difference of squares formula \"A%5E2-B%5E2=%28A%2BB%29%28A-B%29\" to factor the expression:\r
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\n" ); document.write( "\n" ); document.write( "\"A%5E2-B%5E2=%28A%2BB%29%28A-B%29\" Start with the difference of squares formula.\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%29%5E2-%282%29%5E2=%283x%2B2%29%283x-2%29\" Plug in \"A=3x\" and \"B=2\".\r
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\n" ); document.write( "\n" ); document.write( "So this shows us that \"9x%5E2-4\" factors to \"%283x%2B2%29%283x-2%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words \"9x%5E2-4=%283x%2B2%29%283x-2%29\".\r
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\n" ); document.write( "\n" ); document.write( "So this confirms our answer
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