document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=69359>Question 69359</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how do you calculate the surface area of a cone with height of 18 ft and r of 10 ft </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #49412 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=49412\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I presume that you are thinking of a right-circular cone ... that is, a cone whose height (h) is measured along a line perpendicular to the base that goes through the center of the circular base and through the vertex of the cone.\r<BR>\n" );
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document.write( "The formula for this surface area is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S+=+%28pi%29%2Ar%2As ALIGN=MIDDLE  ALT=\"S+=+%28pi%29%2Ar%2As\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "where the variables in the equation are defined as: S is the surface area; r is the radius of the circle that forms the base; and s is the slant length of a line that goes from the perimeter of the circle forming the base to the vertex.\r<BR>\n" );
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document.write( "By the way of explanation the length of s is the hypotenuse of a right triangle whose legs are r and h where h is the length of the perpendicular between the center of the circular base and the vertex. \r<BR>\n" );
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document.write( "For your problem, you are given that the radius of the circular base is 10 feet and the height of the cone is 18 feet.  From this calculate s using the Pythagorean theorem:\r<BR>\n" );
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document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2810%5E2+%2B+18%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%2810%5E2+%2B+18%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28100+%2B+324%29 ALIGN=MIDDLE  ALT=\"sqrt%28100+%2B+324%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28424%29 ALIGN=MIDDLE  ALT=\"sqrt%28424%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 20.5913 ft\r<BR>\n" );
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document.write( "Next substitute the known values of the variables into the surface area formula:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S+=+%28pi%29%2Ar%2As ALIGN=MIDDLE  ALT=\"S+=+%28pi%29%2Ar%2As\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S+=+%28pi%29%2A10%2A20.5913 ALIGN=MIDDLE  ALT=\"S+=+%28pi%29%2A10%2A20.5913\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "When you do the multiplication you find that the surface area is 646.895 square feet. </SPAN>\n" );
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