document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=18511>Question 18511</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the area of an equilateral triangle whose vertices lie on a circle with radius 2cm. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #26027 by </B><A HREF=/tutors/aboutme.mpl?userid=tran3209><B>tran3209(100)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tran3209><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=26027\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let ABC be the equilateral triangle whose verticle lie on the circle with a radius of 2cm and \"O\" as the center.\r<BR>\n" );
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document.write( "AH the perpendicular from A to BC is the altitude\r<BR>\n" );
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document.write( "In an equilateral triangle the altitude is also the median.\r<BR>\n" );
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document.write( "So O is also the centroid of the triangle \r<BR>\n" );
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document.write( "So ---->OH/AO = ½<BR>\n" );
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document.write( "OH= OA/2 = 2/2 = 1cm\r<BR>\n" );
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document.write( "AH=2+1=3cm\r<BR>\n" );
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document.write( "In the triange OCH\r<BR>\n" );
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document.write( "OC=2cm\r<BR>\n" );
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document.write( "OH=1cm\r<BR>\n" );
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document.write( "apply the pythagorean theorem\r<BR>\n" );
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document.write( "OC^2= OH^2 + HC^2<BR>\n" );
document.write( "or<BR>\n" );
document.write( "HC^2 =OC^2 - OH^2\r<BR>\n" );
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document.write( "=2^2-1^2\r<BR>\n" );
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document.write( "=4-1=3<BR>\n" );
document.write( "HC = &#8730;3\r<BR>\n" );
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document.write( "The side of the triangle BC =2HC = 2&#8730;3\r<BR>\n" );
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document.write( "The area of the triangle:\r<BR>\n" );
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document.write( "AH X BC<BR>\n" );
document.write( "-------<BR>\n" );
document.write( "   2<BR>\n" );
document.write( "= 2 X 2&#8730;3<BR>\n" );
document.write( " --------<BR>\n" );
document.write( "    2\r<BR>\n" );
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document.write( "= 4&#8730;3<BR>\n" );
document.write( " -----<BR>\n" );
document.write( "   2<BR>\n" );
document.write( "Area of the triangle is 2&#8730;3 cm^2<BR>\n" );
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