document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=147273>Question 147273</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Triangle ABC is isosceles with AB congruent to AC. Extend segment BA to a point T (in other wordds, A should be between B and T.) Prove that angle TAC must be twice the size of angle ABC. Angle TAC is called one of the exterior angles of triangle ABC. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #107666 by </B><A HREF=/tutors/aboutme.mpl?userid=Nate><B>Nate(3500)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Nate><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=107666\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Angles CBA and BCA will be known as \"x\", then:<BR>\n" );
document.write( "BAC = 180 - 2x<BR>\n" );
document.write( "TAC = 180 - BAC<BR>\n" );
document.write( "TAC = 180 - ( 180 - 2x )<BR>\n" );
document.write( "TAC = 2x while ABC = x </SPAN>\n" );
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