document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=132796>Question 132796</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given: angle 1 and angle 2 form a linear pair <BR>\n" );
document.write( "       angle 2 + angle 3 + angle 4 = 180\r<BR>\n" );
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document.write( "Prove: angle 1 = angle 3 and angle4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #97036 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=97036\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Linear pairs of angles are supplementary, meaning that the sum of their measures is 180.\r<BR>\n" );
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document.write( "That means that a1 + a2 = 180, which we can write as a1 = 180 - a2.\r<BR>\n" );
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document.write( "But we also know that a2 + a3 + a4 = 180, which we can write as a3 + a4 = 180 - a2.\r<BR>\n" );
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document.write( "Since a = b and c = b if and only if a = c, a3 + a4 = a1. </SPAN>\n" );
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