document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=71253>Question 71253</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The price of gasoline at a local station throughout the month of March is modeled by y=-0.014x^2+0.448x-2.324 where x=1 corresponds to March 1.<BR>\n" );
document.write( "a) On what day in March did the price of gasoline reach it's maximum?<BR>\n" );
document.write( "b) What was the highest price of gasoline in March? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #50959 by </B><A HREF=/tutors/aboutme.mpl?userid=funmath><B>funmath(2933)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=funmath><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=50959\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The price of gasoline at a local station throughout the month of March is modeled by y=-0.014x^2+0.448x-2.324 where x=1 corresponds to March 1.<BR>\n" );
document.write( "a) On what day in March did the price of gasoline reach it's maximum?<BR>\n" );
document.write( "What you need to find is the vertex of the parabola represented by this function.  The formula to find the vertex of a parabola represented by a quadratic function in the form of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=ax%5E2%2Bbx%2Bc%29 ALIGN=MIDDLE  ALT=\"highlight%28y=ax%5E2%2Bbx%2Bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=-b%2F2a%29 ALIGN=MIDDLE  ALT=\"highlight%28x=-b%2F2a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " a=-0.041 and b=0.448, so the price of gasoline reaches its maximum at:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-0.448%2F%282%28-0.014%29%29 ALIGN=MIDDLE  ALT=\"x=-0.448%2F%282%28-0.014%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=16 ALIGN=MIDDLE  ALT=\"x=16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Therefore the price reaches it's maximum on March 16. <BR>\n" );
document.write( "b) What was the highest price of gasoline in March?<BR>\n" );
document.write( "What you need to find is the y value of the vertex of the parabola.  You can get this by plugging the x value of the parabola into the function for x and solve for y.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-0.014%2816%29%5E2%2B0.448%2816%29-2.324 ALIGN=MIDDLE  ALT=\"y=-0.014%2816%29%5E2%2B0.448%2816%29-2.324\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=1.26 ALIGN=MIDDLE  ALT=\"y=1.26\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You didn't mention how you were measuring the price of gasoline, it appears that the maximum price is $1.26 per gallon.<BR>\n" );
document.write( "Happy Calculating!!! </SPAN>\n" );
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