document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=288215>Question 288215</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The amount of background noise is important to television news reporters. One station developed the formula n= -t^2 + 12t +54 showing the noise level in decibels (N) as it relates to the time after the speaker stops talking in seconds (t). How many seconds after the speaker stops will the noise level<BR>\n" );
document.write( "be the greatest? Write and tell how you decided. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #208922 by </B><A HREF=/tutors/aboutme.mpl?userid=amnd><B>amnd(23)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=amnd><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=amnd><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=208922\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can find the amount of seconds (t) that would lead to the maximum noise level (N) by finding its derivative through differentiation, or N'. <u>At maximum N, N' would have a value of zero.</u> \r<BR>\n" );
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document.write( "For <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N+=+-t%5E2+%2B+12t+%2B54 ALIGN=MIDDLE  ALT=\"N+=+-t%5E2+%2B+12t+%2B54\"   DISABLED_style= \"max-width:90%; height:auto;\" >, N'=-2t+12\r<BR>\n" );
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document.write( "As N'=0:\r<BR>\n" );
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document.write( "-2t+12=0, yielding <b>t = 6 seconds</b>\r<BR>\n" );
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document.write( "You can try inputting various values for t and compare them (for example, 5, 6 and 7), and it would yield the same result. </SPAN>\n" );
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