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<div>:: <span class="kw">deftheorem </span>   defines <a href="gtarski5.html#K1" title="GTARSKI5:func.1">half-plane</a> <a onclick="hs(this)" href="javascript:()">GTARSKI5:def 7 : <br/></a><span> for <font color="Olive" title="b1">S</font> being   non  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>   <a href="gtarski1.html#L1" title="GTARSKI1:struct.1">TarskiGeometryStruct</a> <br/>  for <font color="Olive" title="b2">A</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Olive" title="b1">S</font><br/>  for <font color="Olive" title="b3">a</font> being   <a href="gtarski1.html#NM1" title="GTARSKI1:NM.1">POINT</a> of <font color="Olive" title="b1">S</font> holds   <a href="gtarski5.html#K1" title="GTARSKI5:func.1">half-plane</a> (<font color="Olive" title="b2">A</font>,<font color="Olive" title="b3">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <font color="Olive" title="b4">x</font> where <font color="Olive" title="b4">x</font> is   <a href="gtarski1.html#NM1" title="GTARSKI1:NM.1">POINT</a> of <font color="Olive" title="b1">S</font> : <font color="Olive" title="b2">A</font> <a href="gtarski5.html#R5" title="GTARSKI5:pred.5">out</a> <font color="Olive" title="b4">x</font>,<font color="Olive" title="b3">a</font> </span> } </span> ;<br/></span></div>
