document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=131506>Question 131506</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The number of mosquitoes M(x), in millions, in a certain area depends on the June rainfall x, in inches: M(x)=19x-x^2. What rainfall produces the maximum number of mosquitoes? Hint: Find the maximum of the parabola. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #95994 by </B><A HREF=/tutors/aboutme.mpl?userid=AdolphousC><B>AdolphousC(70)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=AdolphousC><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=95994\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You need either a calculator or some paper and pencil for this one. If you have a calc plug the equation into the y= and use 2nd trace maximum.\r<BR>\n" );
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document.write( "If you don't have a calculator then you first need to find the zeros. This is easy using factoring.\r<BR>\n" );
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document.write( "19x-x^2\r<BR>\n" );
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document.write( "Factor out an x x(19-x) set each to zero.<BR>\n" );
document.write( "x = 0 and x = 19.\r<BR>\n" );
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document.write( "those are where the parabola crosses the x-axis. Since parabolas are symmetrical, the x value of the max falls 1/2 way between the zeros at 9.5\r<BR>\n" );
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document.write( "Plug in 9.5 for x in the original equation. Solve for the number of Mosquitos and there is your answer. </SPAN>\n" );
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