document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=248947>Question 248947</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Here's another word problem I'm having trouble with. Again, I feel like I know how to do this but I can't get the right equation to start with. If nothing else could you please help me get the right equation. I would greatly appreciate it!\r<BR>\n" );
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document.write( "Problem: A window consists of an open rectangle topped by a semicircle and is to have a perimeter of 288 inches. Find the radius of the semicircle that will maximize the area of the window.\r<BR>\n" );
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document.write( "I drew a picture and labeled it the best I could. I wrote down that the perimeter of a circle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2Api%2Ar ALIGN=MIDDLE  ALT=\"2%2Api%2Ar\"   DISABLED_style= \"max-width:90%; height:auto;\" > I also wrote that the perimeter of a rectangle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2l%2B2w ALIGN=MIDDLE  ALT=\"2l%2B2w\"   DISABLED_style= \"max-width:90%; height:auto;\" > but that's about all that I could do. Please help! Thank you in advance for your help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #181420 by </B><A HREF=/tutors/aboutme.mpl?userid=dabanfield><B>dabanfield(803)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dabanfield><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=181420\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If this isn't a calculus problem then we need to use the fact that a square maximizes the area for a rectangle with a given perimeter. Let's say the half circle at the top is R. Then each side of the square is 2*R. \r<BR>\n" );
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document.write( "The perimeter of the semi-circle is half the circumference so that is 1/2(2*pi*R) which is then pi*R.\r<BR>\n" );
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document.write( "So the entire perimeter is given by:\r<BR>\n" );
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document.write( "pi*R + 3*(2*R)= 388.\r<BR>\n" );
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document.write( "Now you can solve for R. </SPAN>\n" );
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