document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1177468>Question 1177468</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two- column proof.\r<BR>\n" );
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document.write( "https://ibb.co/xqFqMX5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #806518 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=806518\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "mangle 1 + m angle2 + m angle 3 = 180 deg.  Sum of angles of triangle = 180 deg.\r<BR>\n" );
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document.write( "mangle 3 + mangle 4 = 180 deg. angles in a linear pair\r<BR>\n" );
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document.write( "Therefore \r<BR>\n" );
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document.write( "mangle 1 + m angle2 + m angle 3 = mangle 3 + mangle 4\r<BR>\n" );
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document.write( "m angle 3 is common\r<BR>\n" );
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document.write( "mangle 1 + m angle2  = mangle 4  \r<BR>\n" );
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