document.write( "Question 293645: if f(x)=x^2+2x
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Algebra.Com's Answer #211932 by jim_thompson5910(35256)\"\" \"About 
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\"f%28x%29=x%5E2%2B2x\" Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28a%2B3%29=%28a%2B3%29%5E2%2B2%28a%2B3%29\" Plug in \"x=a%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%28a%2B3%29=a%5E2%2B6a%2B9%2B2%28a%2B3%29\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"f%28a%2B3%29=a%5E2%2B6a%2B9%2B2a%2B6\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28a%2B3%29=a%5E2%2B8a%2B15\" Combine like terms.
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