document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=62782>Question 62782</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am trying to write a proof for a Geometry problem and can not figure the proof out.  Given triangle ABC is equilateral then prove m<A=60 degree, m<B=60 degreee, m<C=60 degree.  I was told it would take 10 steps to solve the proof?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #43619 by </B><A HREF=/tutors/aboutme.mpl?userid=jai_kos><B>jai_kos(139)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jai_kos><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=43619\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Consider an equilateral triangle,\r<BR>\n" );
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document.write( "all the sides are equal.\r<BR>\n" );
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document.write( "Let the all the sides of triangle = 1cm\r<BR>\n" );
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document.write( "And A be the angle of the first side,<BR>\n" );
document.write( "B be the third angle for the second side.<BR>\n" );
document.write( "c be the second angle for the third side<BR>\n" );
document.write( "Now we know the sine rule,\r<BR>\n" );
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document.write( "SinA / first side = Sin B /second side = SinC /third side \r<BR>\n" );
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document.write( "SinA /1 = sinB / 1 = Sin C/1\r<BR>\n" );
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document.write( "SinA =SinB =SinC\r<BR>\n" );
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document.write( "A =B=C<BR>\n" );
document.write( "We know that the sum of the triangle is equal to 180 degree,\r<BR>\n" );
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document.write( "angleA+ angleB + angle C = 180\r<BR>\n" );
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document.write( "Since all the angles are same,\r<BR>\n" );
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document.write( "We write  the above equation as,\r<BR>\n" );
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document.write( "3angle A = 180\r<BR>\n" );
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document.write( "angle A =180 /3 = 60\r<BR>\n" );
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document.write( "Angle A =angleB=Anglec= 60\r<BR>\n" );
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document.write( "or measure of A = 60\r<BR>\n" );
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document.write( "   measure of B =60<BR>\n" );
document.write( "   <BR>\n" );
document.write( "   measure of c = 60<BR>\n" );
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