document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=78059>Question 78059</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plastic cover is made for a pool with a diameter of 24 feet. The cover will rest on the top of the pool and will include a wedge-shaped flap that forms a 45 degree angle at the center of the cover. A zipper will go along 1 side of the wedge-shape flap and around the arc. Which of the following is closest to the length, in feet, of the zipper?<BR>\n" );
document.write( "-I know that 12 feet is the length of one radius so that is part of the length of the zipper. I am not sure how to find the length of the arc on a circle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55974 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=55974\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To find the arc length simply use this formula:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large s=\theta*r\"> where <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large \theta\"> is the angle\r<BR>\n" );
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document.write( "So lets find the arc length with the given information:\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=Arc_Length.solver>Arc Length</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT> <A  rel=nofollow HREF=Central_angle.wikipedia>Angle at center described by an Arc</A><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  The angle described by an arc at center is 45 degrees.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <A  rel=nofollow HREF=Geometry-Arcs-and-Chords.lesson>Arc of a circle</A><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  The Length of Arc is given by formula <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Length+=+pi%2Aradius%2Acentral+angle%2F180 ALIGN=MIDDLE  ALT=\"Length+=+pi%2Aradius%2Acentral+angle%2F180\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
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document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Length+=+pi%2A12%2A45%2F180=9.42477795 ALIGN=MIDDLE  ALT=\"Length+=+pi%2A12%2A45%2F180=9.42477795\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Conversion of angles from <b><A  rel=nofollow HREF=Degree_%28angle%29.wikipedia>degrees</A></b> to <b><A  rel=nofollow HREF=Radian.wikipedia>radian</A></b>:<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  The relation between two units of angle measurement is :<BR>\n" );
document.write( "   <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  2*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi ALIGN=MIDDLE  ALT=\"pi\"   DISABLED_style= \"max-width:90%; height:auto;\" > rad = 360 degrees<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Area of Arc when angle in radians is,<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Length=Central+angle%2Aradius ALIGN=MIDDLE  ALT=\"Length=Central+angle%2Aradius\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Length=0.7853981625%2A12=9.42477795 ALIGN=MIDDLE  ALT=\"Length=0.7853981625%2A12=9.42477795\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
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document.write( "  Hence, For a Circle of radius 12 the Arc length is 9.42477795 when it subtends an angle of 45 degrees at center.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <BR>\n" );
document.write( "  For more on this topic, See the lessons on <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Circles/Lessons.html>Circles and their properties</A><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Some relevant <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Circles/InDepth.html>wikipedia</A> articles for the topic.<BR>\n" );
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document.write( "So our arc length is 9.424778 ft\r<BR>\n" );
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document.write( "Since the zipper goes from the center to the arc, simply add the arc length and the radius to find the total length of the zipper:\r<BR>\n" );
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document.write( "12+9.424778=21.424778 ft\r<BR>\n" );
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document.write( "So if you wanted this length rounded to the closest foot you would get:\r<BR>\n" );
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document.write( "lenght of zipper=21 ft </SPAN>\n" );
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