document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1011972>Question 1011972</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In &#916;ABC, AB = CB and D is on AB such that AC = DC. If m&#8736;ADC = 75, what is m&#8736;B?\r<BR>\n" );
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document.write( "Sorry if its messy, but I attempted it and got stuck. My work so far was that if CA is congruent to CD then the triangle is isosceles so therefore &#8736;CAD is congruent to &#8736;CDA. Because &#8736;CDA was given as 75 degrees in the given I also know &#8736;CAD is 75 degrees. Also because &#8736;CDA and &#8736;CDB form a linear pair, they are also supplementary so I subtract 75 (&#8736;CDB) from 180 to get &#8736;CDB which is 105. As I know the interior angles add up to the exterior angle I did 105 - 75 which gives me &#8736;ACD which is 30 degrees. \r<BR>\n" );
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document.write( "This is where I get stuck and have no idea how to find &#8736;B. I do not think I can use the ext. angle thm. as I do not know &#8736;DCB. Please help me out! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #627800 by </B><A HREF=/tutors/aboutme.mpl?userid=macston><B>macston(5194)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=macston><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=macston><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=627800\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Triangle ABC is isosceles, with angle CAB=angle ACB.<BR>\n" );
document.write( "Triangle ADC is isosceles with angle CAD=angle CDA.<BR>\n" );
document.write( "Given angle CDA=75 degrees, angles CAB (&#8736;A) and ACB (&#8736;C) also equal 75 degrees.<BR>\n" );
document.write( "Angles CAB (&#8736;A), and CBA (&#8736;B), ACB (&#8736;C) form the triangle ABC, <BR>\n" );
document.write( "thus their sum is 180 degrees:<BR>\n" );
document.write( "&#8736;A + &#8736;B + &#8736;C = 180 degrees<BR>\n" );
document.write( "75 degrees  + &#8736;B + 75 degrees = 180 degrees<BR>\n" );
document.write( "&#8736;B = 30 degrees<BR>\n" );
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document.write( "ANSWER The measure of Angle B is 30 degrees.<BR>\n" );
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