document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1089989>Question 1089989</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given:	<1 is congruent to <2; < 1 and <2 are supplementary.    	\r<BR>\n" );
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document.write( "Prove: <1 & <2 are right angles.\r<BR>\n" );
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document.write( "(picture: http://imgur.com/WxNdiTh\r<BR>\n" );
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document.write( "<1 is congruent to <2	(Given)<BR>\n" );
document.write( "<1 & <2 are supplementary	(Given)<BR>\n" );
document.write( "m<1 = m<2	(Definition of congruent angles)<BR>\n" );
document.write( "m<1 + m<2= 180	(?) <BR>\n" );
document.write( "m<1 + m<1= 180	(Substitution Property)<BR>\n" );
document.write( "2(m<1) = 180	(Substitution Property)<BR>\n" );
document.write( "2(m<1)/2 = 180/2	(Multiplication/Division Property)<BR>\n" );
document.write( "m<1 = 90	(Substitution Property)<BR>\n" );
document.write( "m<2 = 90	 (?)<BR>\n" );
document.write( "<1 and <2 are right angles	(Definition of right angles)<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 #704401 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=704401\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=\"black\" face=\"times\" size=\"3\"><BR>\n" );
document.write( "If \"< 1 & < 2 are supplementary\" is given, then what immediately follows is that \"m < 1 + m < 2 = 180\" by the <font color=red>definition of supplementary angles</font>. In other words, if two angles are supplementary, then they add to 180 degrees. \r<BR>\n" );
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document.write( "If m < 1 = m < 2, and m < 1 = 90, then m < 2 = 90 as well through the <font color=red>substitution property</font> (or you could argue the transitive property of equality which is very similar). You can think of it as starting off with m < 1 = m < 2, then replacing the \"m < 1\" with \"90\". This replacement is valid because of m < 1 = 90.<BR>\n" );
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