document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=280329>Question 280329</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dear Sir,  Please help me!\r<BR>\n" );
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document.write( "ABCDEFGH is a regular octagon calculate ABC ACD ABD angles </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #203739 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=203739\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ABCDEFGH is a regular octagon.\r<BR>\n" );
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document.write( "If so, then each interior angle is the same.\r<BR>\n" );
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document.write( "Each angle of an octagon can be found using the following general formula:\r<BR>\n" );
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document.write( "i = ((n-2)*180)/n where i = each interior angle and n = number of sides.\r<BR>\n" );
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document.write( "In a triangle, n = 3, and each interior angle would be 1*180/3 = 60 degrees.\r<BR>\n" );
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document.write( "In a rectangle, n = 4, and each interior angle would be 2*180/4 = 90 degrees.\r<BR>\n" );
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document.write( "In an octagon, n = 8, and each interior angle would be 6*180/8 = 1080/8 = 135 degrees.\r<BR>\n" );
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document.write( "Now your octagon is labeled ABCDEFGH.\r<BR>\n" );
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document.write( "You want to find the measure of:\r<BR>\n" );
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document.write( "ABC<BR>\n" );
document.write( "ACD<BR>\n" );
document.write( "ABD\r<BR>\n" );
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document.write( "Angle ABC is one of the interior angles so angle ABC equals 135 degrees.\r<BR>\n" );
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document.write( "A picture of angle ABC is shown below:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/problems/280329p1.jpg\" alt = \"********** PICTURE DID NOT DISPLAY PROPERLY **********\" />\r<BR>\n" );
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document.write( "Angle ACD = 112.5 degrees as shown in the following picture.\r<BR>\n" );
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document.write( "As you can see, Angle ACD creates a small triangle ABC.   Since this is a regular polygon, then triangle ABC is an isosceles triangle.   Since angle ABC is 135 degrees, the other 2 angles of the triangle have to be (180-135)/2 which equals 22.5 degrees.   Since angle BCD is also equal to 135 degrees, and angle BCA is equal to 22.5 degrees, then angle ACD is equal to 135 minus 22.5 = 112.5 degrees.\r<BR>\n" );
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document.write( "Angle ABD = 112.5 degrees as shown in the following picture.\r<BR>\n" );
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document.write( "As you can see, Angle ABD creates a small triangle BCD.   Since this is a regular polygon, then triangle BCD is an isosceles triangle.   Since angle BCD is 135 degrees, the other 2 angles of the triangle have to be (180-135)/2 which equals 22.5 degrees.   Since angle ABC is also equal to 135 degrees, and angle CBD is equal to 22.5 degrees, then angle ABD is equal to 135 minus 22.5 = 112.5 degrees.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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