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<b>let </b><font color="Maroon">SAS</font> be   <a href="semi_af1.html#NM1">Semi_Affine_Space</a>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">SAS</font>;<br/><b>let </b><font color="Maroon">o</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">SAS</font>;<br/>





<a NAME="E1:85"/>
(  <a href="semi_af1.html#K1" target="_self">sum</a> <font color="Maroon">a</font>,<span class="p1">(<span class="default"><a href="semi_af1.html#K2" target="_self">opposite</a> <font color="Maroon">a</font>,<font color="Maroon">o</font></span>)</span>,<font color="Maroon">o</font> <a href="hidden.html#R1">=</a> <font color="Maroon">o</font> &amp;  <a href="semi_af1.html#R3" target="_self">congr</a> <font color="Maroon">o</font>,<font color="Maroon">a</font>, <a href="semi_af1.html#K2" target="_self">opposite</a> <font color="Maroon">a</font>,<font color="Maroon">o</font>, <a href="semi_af1.html#K1" target="_self">sum</a> <font color="Maroon">a</font>,<span class="p1">(<span class="default"><a href="semi_af1.html#K2" target="_self">opposite</a> <font color="Maroon">a</font>,<font color="Maroon">o</font></span>)</span>,<font color="Maroon">o</font> )
 
<b>by </b><i><a class="ref" href="semi_af1.html#T40" target="_self">Th40</a>, <a class="ref" href="semi_af1.html#T41" target="_self">Th41</a></i>;<br/>
<b>hence </b><a NAME="E2:85"/>
 <a href="semi_af1.html#R3" target="_self">congr</a> <font color="Maroon">a</font>,<font color="Maroon">o</font>,<font color="Maroon">o</font>, <a href="semi_af1.html#K2" target="_self">opposite</a> <font color="Maroon">a</font>,<font color="Maroon">o</font>
 <b>by </b><i><a class="ref" href="semi_af1.html#T33" target="_self">Th33</a></i>;<br/>


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