document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=134509>Question 134509</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The temperature, T, in degrees Fahrenheit, in a car's radiator during the first 4 minutes of driving is a function of time, t.  The temperature can be found by the formula T=5.8t^2+13t+32, 0 less than or equal to t less than or equal to 4.\r<BR>\n" );
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document.write( "a) What is the car's radiator's temperature at the instant the car is turned on?<BR>\n" );
document.write( "b) What is the car's radiator's temperature after the car has been driven for 3 minutes? <BR>\n" );
document.write( "c) How long after the car has begun operating will the car's radiator temperature reach 90 degrees Fahrenheit?   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #98389 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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=98389\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Given: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=5.8t%5E2%2B13t%2B32 ALIGN=MIDDLE  ALT=\"T=5.8t%5E2%2B13t%2B32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "a) What is the car's radiator's temperature at the instant the car is turned on? What is the time when the car is turned on? time = 0<BR>\n" );
document.write( "So replace t with 0 in the function and solve<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=5.8%2A0%5E2%2B13%2A0%2B32 ALIGN=MIDDLE  ALT=\"T=5.8%2A0%5E2%2B13%2A0%2B32\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T+=+32 ALIGN=MIDDLE  ALT=\"T+=+32\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "b) What is the car's radiator's temperature after the car has been driven for 3 minutes? <BR>\n" );
document.write( "What value should yo use for t now? t = 3<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=5.8%2A3%5E2%2B13%2A3%2B32 ALIGN=MIDDLE  ALT=\"T=5.8%2A3%5E2%2B13%2A3%2B32\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T+=+5.8%2A9+%2B+13%2A3+%2B+32 ALIGN=MIDDLE  ALT=\"T+=+5.8%2A9+%2B+13%2A3+%2B+32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T+=+123.2 ALIGN=MIDDLE  ALT=\"T+=+123.2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "c) How long after the car has begun operating will the car's radiator temperature reach 90 degrees Fahrenheit?  <BR>\n" );
document.write( "This time you are given a tempurature (T) and asked to find the time.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=90=5.8t%5E2%2B13t%2B32 ALIGN=MIDDLE  ALT=\"90=5.8t%5E2%2B13t%2B32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+5.8t%5E2+%2B+13t+-+58 ALIGN=MIDDLE  ALT=\"0+=+5.8t%5E2+%2B+13t+-+58\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Use the quadratic equation to find values for t. Then pick the value that 'makes sense\"<BR>\n" );
document.write( "0 = at^2 + bt + c, so a = 5.8, b = 13 and c = -58<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "I get t = 2.24\r<BR>\n" );
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document.write( "Check your answer by replacing t with 2.23<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T+=+5.8%2A+2.24%5E2+%2B+13+%2A+2.24+%2B+32 ALIGN=MIDDLE  ALT=\"T+=+5.8%2A+2.24%5E2+%2B+13+%2A+2.24+%2B+32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T+=+29.01+%2B+29.12+%2B+32+ ALIGN=MIDDLE  ALT=\"T+=+29.01+%2B+29.12+%2B+32+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  ~ 90<BR>\n" );
document.write( " </SPAN>\n" );
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