document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=281471>Question 281471</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the area of an equilateral triangle (regular 3 gon) with the given measurement.<BR>\n" );
document.write( "9 inch perimeter<BR>\n" );
document.write( "Area= what?<BR>\n" );
document.write( "pllz help! :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #204490 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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/cgi-bin/show-face.mpl?user=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=204490\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What does the fact that the triangle is equilateral tell you?\r<BR>\n" );
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document.write( "What does the perimeter of 9 inches tell you?<BR>\n" );
document.write( "so we have a triangle with three sides equal to 3.<BR>\n" );
document.write( "if we drop  a bisecting line from one vertex to the opposite side we form a right triangle with hypotenuse 3 and the base is 1.5.<BR>\n" );
document.write( "the missing side (bisecting line)  will be the height of the of the triangle<BR>\n" );
document.write( "a=1/2 base (1.5) times the height which we can find using the pythagorean theorem or the 30 60 90 triangle features<BR>\n" );
document.write( "1.5^2+h^2=3^2<BR>\n" );
document.write( "h^2=6.74<BR>\n" );
document.write( "h=2.598<BR>\n" );
document.write( "which we could have gotten from sqrt(3)*(1.5)  a relationship of 30 60 90 triangles<BR>\n" );
document.write( "so the height is sqrt(3)*1.5<BR>\n" );
document.write( "and the base is 1.5\r<BR>\n" );
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document.write( "a=.5*b*h<BR>\n" );
document.write( "a=.5*1.5^2*sqrt(3)<BR>\n" );
document.write( "or a=.5*1.5*2.598<BR>\n" );
document.write( "a=1.95<BR>\n" );
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