document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=882262>Question 882262</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Trying to help my son figure out surface area of a cylinder. <BR>\n" );
document.write( "What is the surface area if the radius is 4 ft. and the height is 21 ft.<BR>\n" );
document.write( "Do you do as follows:<BR>\n" );
document.write( "2(3.14)(8)+ 2(3.14)(4)(21) = 577.76.<BR>\n" );
document.write( "Not sure that is correct. Where are we going wrong?<BR>\n" );
document.write( "Tx for your help!!!! Final tomorrow :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #532750 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=532750\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+2%2Api%2Ar%5E2+%2B+2%2Api%2Ar%2Ah ALIGN=MIDDLE  ALT=\"SA+=+2%2Api%2Ar%5E2+%2B+2%2Api%2Ar%2Ah\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+2%2Api%2A4%5E2+%2B+2%2Api%2A4%2A21 ALIGN=MIDDLE  ALT=\"SA+=+2%2Api%2A4%5E2+%2B+2%2Api%2A4%2A21\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+2%2Api%2A16+%2B+2%2Api%2A4%2A21 ALIGN=MIDDLE  ALT=\"SA+=+2%2Api%2A16+%2B+2%2Api%2A4%2A21\"   DISABLED_style= \"max-width:90%; height:auto;\" > Here's where you made the mistake. You computed <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%5E2+=+8 ALIGN=MIDDLE  ALT=\"4%5E2+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > when it *should* have been <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%5E2+=+16 ALIGN=MIDDLE  ALT=\"4%5E2+=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+2%2A16%2Api+%2B+2%2A4%2A21%2Api ALIGN=MIDDLE  ALT=\"SA+=+2%2A16%2Api+%2B+2%2A4%2A21%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+32%2Api+%2B+168%2Api ALIGN=MIDDLE  ALT=\"SA+=+32%2Api+%2B+168%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+200pi ALIGN=MIDDLE  ALT=\"SA+=+200pi\"   DISABLED_style= \"max-width:90%; height:auto;\" > <font color=\"red\"><--- Exact Surface Area</font> (in terms of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi ALIGN=MIDDLE  ALT=\"pi\"   DISABLED_style= \"max-width:90%; height:auto;\" >)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+200%2A%283.14%29 ALIGN=MIDDLE  ALT=\"SA+=+200%2A%283.14%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=SA+=+628 ALIGN=MIDDLE  ALT=\"SA+=+628\"   DISABLED_style= \"max-width:90%; height:auto;\" > <font color=\"blue\"><--- Approximate Surface Area</font> (using the approximation <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \pi \approx 3.14\">)\r<BR>\n" );
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document.write( "Note: to get a better approximation, use more digits of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi ALIGN=MIDDLE  ALT=\"pi\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Another Note: the units of the final answer are in square feet. </SPAN>\n" );
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