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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E32">Th31</font></span>: <a NAME="T38"><span class="comment"><font color="firebrick">:: EUCLID13:38</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font>, <font color="Olive" title="b2">B</font>, <font color="Olive" title="b3">C</font> being   <a href="pre_topc.html#NM2" title="PRE_TOPC:NM.2">Point</a> of <span class="p1">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> 2</span>)</span>  st <font color="Olive" title="b2">B</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b3">C</font> holds <br/> <a href="euclid13.html#K1" title="EUCLID13:func.1">the_altitude</a> (<font color="Olive" title="b1">A</font>,<font color="Olive" title="b2">B</font>,<font color="Olive" title="b3">C</font>) is  <a href="euclid_4.html#V1" title="EUCLID_4:attr.1">being_line</a> </div></div>
