document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=753552>Question 753552</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The pyramid in the diagram below has a square base, 40 feet on each side. Its slant height is 160 feet. What is the surface area of the pyramid? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #458458 by </B><A HREF=/tutors/aboutme.mpl?userid=malglu><B>malglu(63)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=malglu><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=458458\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The pyramid in the diagram below has a square base, 40 feet on each side. Its slant height is 160 feet. What is the surface area of the pyramid?\r<BR>\n" );
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document.write( "first you need the area of the base, which is 40foot * 40 foot.  then you need to add this to 4 * the surface area of one of the sides.  these sides are triangler in shape.  the base is 40 foot and the two slanting sides are 160 feet.  the area of a traingle is 1/2 * base * perpendicular height.  use pythagurus's theorem to calculate the perpendicular height.  160 ^2 = 40 ^2 + x^2 (the perpendicular height)\r<BR>\n" );
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document.write( "25600 - 1600 = x^2<BR>\n" );
document.write( "24000 = x^2<BR>\n" );
document.write( "take roots of each side<BR>\n" );
document.write( "x = 154.99 to 2 dp\r<BR>\n" );
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document.write( "now 1/2 * base (40) * 154.99 = 3098.39 to 2 dp<BR>\n" );
document.write( "* 4 = 12393.55<BR>\n" );
document.write( "+ 1600 (area of base) = 13993.55 squared feet to 2 dp<BR>\n" );
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