document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=78037>Question 78037</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For a chemical reaction, temperature is a function of time.  For Denver Poweroxide this function is T = -t^2 + 7t + 8 (T is degrees Fahrenheit and t is seconds).  How long will it take for the temperature to reach zero?  Solve by graphing.\r<BR>\n" );
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document.write( "I got: 1 second. Is this correct?<BR>\n" );
document.write( "Thanks~ </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55928 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=55928\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> T = -t^2 + 7t + 8<BR>\n" );
document.write( "T=-0<BR>\n" );
document.write( "-t^2+2t+8=0<BR>\n" );
document.write( "Multiply thru by -1 to get:<BR>\n" );
document.write( "t^2-2t-8=0<BR>\n" );
document.write( "Factor to get:<BR>\n" );
document.write( "(t-4)(t+2)=0<BR>\n" );
document.write( "t=4 seconds is the only positive answer.<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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