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<b>let </b><font color="Maroon" title="c1">AS</font> be   <a href="diraf.html#NM1" title="DIRAF:NM.1">AffinSpace</a>;<br/><b>let </b><font color="Maroon" title="c2">K</font>, <font color="Maroon" title="c3">P</font>, <font color="Maroon" title="c4">Q</font> be   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">AS</font>;<br/>







<b>assume </b><b>that </b><br/><a NAME="E1:29"/><i><font color="Green" title="E24">A1</font></i>: 
( <font color="Maroon" title="c2">K</font> <a href="aff_1.html#NR2" title="AFF_1:NR.2">is_line</a>  &amp; <font color="Maroon" title="c3">P</font> <a href="aff_1.html#NR2" title="AFF_1:NR.2">is_line</a>  &amp; <font color="Maroon" title="c4">Q</font> <a href="aff_1.html#NR2" title="AFF_1:NR.2">is_line</a>  )
 <b>and </b><br/><a NAME="E2:29"/><i><font color="Green" title="E25">A2</font></i>: 
<font color="Maroon" title="c4">Q</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="aff_4.html#K1" title="AFF_4:func.1">Plane</a> <font color="Maroon" title="c2">K</font>,<font color="Maroon" title="c3">P</font>
 ;<br/>

<b>consider </b><font color="Maroon" title="c5">a</font>, <font color="Maroon" title="c6">b</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">AS</font><b> such that </b><br/><a NAME="E4:29"/><i><font color="Green" title="E26">A3</font></i>: 
( <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">Q</font> &amp; <font color="Maroon" title="c6">b</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">Q</font> )
 <b>and </b><br/><a NAME="E5:29"/><i><font color="Green" title="E27">A4</font></i>: 
<font color="Maroon" title="c5">a</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Maroon" title="c6">b</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E1:29"><i><font color="Green" title="E24">A1</font></i></a>, <a class="ref" href="aff_1.html#T31" title="AFF_1:th.31">AFF_1:31</a></i>;<br/>
<b>consider </b><font color="Maroon" title="c7">a'</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">AS</font><b> such that </b><br/><a NAME="E7:29"/><i><font color="Green" title="E28">A5</font></i>: 
<font color="Maroon" title="c5">a</font>,<font color="Maroon" title="c7">a'</font> <a href="aff_1.html#R2" title="AFF_1:pred.2">//</a> <font color="Maroon" title="c2">K</font>
 <b>and </b><br/><a NAME="E8:29"/><i><font color="Green" title="E29">A6</font></i>: 
<font color="Maroon" title="c7">a'</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">P</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E2:29"><i><font color="Green" title="E25">A2</font></i></a>, <a class="txt" href="aff_4.html#E4:29"><i><font color="Green" title="E26">A3</font></i></a>, <a class="txt" href="aff_4.html#E17"><i><font color="Green" title="E14">Lm3</font></i></a></i>;<br/>
<b>consider </b><font color="Maroon" title="c8">b'</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">AS</font><b> such that </b><br/><a NAME="E10:29"/><i><font color="Green" title="E30">A7</font></i>: 
<font color="Maroon" title="c6">b</font>,<font color="Maroon" title="c8">b'</font> <a href="aff_1.html#R2" title="AFF_1:pred.2">//</a> <font color="Maroon" title="c2">K</font>
 <b>and </b><br/><a NAME="E11:29"/><i><font color="Green" title="E31">A8</font></i>: 
<font color="Maroon" title="c8">b'</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">P</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E2:29"><i><font color="Green" title="E25">A2</font></i></a>, <a class="txt" href="aff_4.html#E4:29"><i><font color="Green" title="E26">A3</font></i></a>, <a class="txt" href="aff_4.html#E17"><i><font color="Green" title="E14">Lm3</font></i></a></i>;<br/>
<b>consider </b><font color="Maroon" title="c9">A</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">AS</font><b> such that </b><br/><a NAME="E13:29"/><i><font color="Green" title="E32">A9</font></i>: 
<font color="Maroon" title="c7">a'</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c9">A</font>
 <b>and </b><br/><a NAME="E14:29"/><i><font color="Green" title="E33">A10</font></i>: 
<font color="Maroon" title="c2">K</font> <a href="aff_1.html#R4" title="AFF_1:pred.4">//</a> <font color="Maroon" title="c9">A</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E1:29"><i><font color="Green" title="E24">A1</font></i></a>, <a class="ref" href="aff_1.html#T63" title="AFF_1:th.63">AFF_1:63</a></i>;<br/>
<b>consider </b><font color="Maroon" title="c10">M</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">AS</font><b> such that </b><br/><a NAME="E16:29"/><i><font color="Green" title="E34">A11</font></i>: 
<font color="Maroon" title="c8">b'</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c10">M</font>
 <b>and </b><br/><a NAME="E17:29"/><i><font color="Green" title="E35">A12</font></i>: 
<font color="Maroon" title="c2">K</font> <a href="aff_1.html#R4" title="AFF_1:pred.4">//</a> <font color="Maroon" title="c10">M</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E1:29"><i><font color="Green" title="E24">A1</font></i></a>, <a class="ref" href="aff_1.html#T63" title="AFF_1:th.63">AFF_1:63</a></i>;<br/>
<a NAME="E18:29"/><i><font color="Green" title="E36">A13</font></i>: 
( <font color="Maroon" title="c7">a'</font>,<font color="Maroon" title="c5">a</font> <a href="aff_1.html#R2" title="AFF_1:pred.2">//</a> <font color="Maroon" title="c9">A</font> &amp; <font color="Maroon" title="c8">b'</font>,<font color="Maroon" title="c6">b</font> <a href="aff_1.html#R2" title="AFF_1:pred.2">//</a> <font color="Maroon" title="c10">M</font> &amp; <font color="Maroon" title="c9">A</font> <a href="aff_1.html#R4" title="AFF_1:pred.4">//</a> <font color="Maroon" title="c10">M</font> )
 
<b>by </b><i><a class="txt" href="aff_4.html#E7:29"><i><font color="Green" title="E28">A5</font></i></a>, <a class="txt" href="aff_4.html#E10:29"><i><font color="Green" title="E30">A7</font></i></a>, <a class="txt" href="aff_4.html#E14:29"><i><font color="Green" title="E33">A10</font></i></a>, <a class="txt" href="aff_4.html#E17:29"><i><font color="Green" title="E35">A12</font></i></a>, <a class="ref" href="aff_4.html#T3" target="_self" title="AFF_4:th.3">Th3</a>, <a class="ref" href="aff_1.html#T58" title="AFF_1:th.58">AFF_1:58</a></i>;<br/>
<a NAME="E19:29"/><b>then </b><i><font color="Green" title="E37">A14</font></i>: 
( <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c9">A</font> &amp; <font color="Maroon" title="c6">b</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c10">M</font> )
 
<b>by </b><i><a class="txt" href="aff_4.html#E13:29"><i><font color="Green" title="E32">A9</font></i></a>, <a class="txt" href="aff_4.html#E16:29"><i><font color="Green" title="E34">A11</font></i></a>, <a class="ref" href="aff_4.html#T2" target="_self" title="AFF_4:th.2">Th2</a></i>;<br/>
<a NAME="E20:29"/><i><font color="Green" title="E38">A15</font></i>: 
( <font color="Maroon" title="c9">A</font> <a href="aff_1.html#NR2" title="AFF_1:NR.2">is_line</a>  &amp; <font color="Maroon" title="c10">M</font> <a href="aff_1.html#NR2" title="AFF_1:NR.2">is_line</a>  )
 
<b>by </b><i><a class="txt" href="aff_4.html#E14:29"><i><font color="Green" title="E33">A10</font></i></a>, <a class="txt" href="aff_4.html#E17:29"><i><font color="Green" title="E35">A12</font></i></a>, <a class="ref" href="aff_1.html#T50" title="AFF_1:th.50">AFF_1:50</a></i>;<br/>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="29_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:29_1"/>
<font color="Maroon" title="c9">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c10">M</font>
 ;<br/><a NAME="E2:29_1"/><b>then </b>
( <font color="Maroon" title="c6">b</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c9">A</font> &amp; <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c9">A</font> )
 <b>by </b><i><a class="txt" href="aff_4.html#E13:29"><i><font color="Green" title="E32">A9</font></i></a>, <a class="txt" href="aff_4.html#E16:29"><i><font color="Green" title="E34">A11</font></i></a>, <a class="txt" href="aff_4.html#E18:29"><i><font color="Green" title="E36">A13</font></i></a>, <a class="ref" href="aff_4.html#T2" target="_self" title="AFF_4:th.2">Th2</a></i>;<br/><a NAME="E3:29_1"/><b>then </b>
<font color="Maroon" title="c7">a'</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">Q</font>
 <b>by </b><i><a class="txt" href="aff_4.html#E1:29"><i><font color="Green" title="E24">A1</font></i></a>, <a class="txt" href="aff_4.html#E4:29"><i><font color="Green" title="E26">A3</font></i></a>, <a class="txt" href="aff_4.html#E5:29"><i><font color="Green" title="E27">A4</font></i></a>, <a class="txt" href="aff_4.html#E13:29"><i><font color="Green" title="E32">A9</font></i></a>, <a class="txt" href="aff_4.html#E20:29"><i><font color="Green" title="E38">A15</font></i></a>, <a class="ref" href="aff_1.html#T30" title="AFF_1:th.30">AFF_1:30</a></i>;<br/><b>hence </b><a NAME="E4:29_1"/>
 ex <font color="Olive" title="b1">q</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">AS</font> st <br/>( <font color="Olive" title="b1">q</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">P</font> &amp; <font color="Olive" title="b1">q</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">Q</font> )
 <b>by </b><i><a class="txt" href="aff_4.html#E8:29"><i><font color="Green" title="E29">A6</font></i></a></i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E22:29"/>
( <font color="Maroon" title="c3">P</font> <a href="aff_1.html#R4" title="AFF_1:pred.4">//</a> <font color="Maroon" title="c4">Q</font> or  ex <font color="Olive" title="b1">q</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">AS</font> st <br/>( <font color="Olive" title="b1">q</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">P</font> &amp; <font color="Olive" title="b1">q</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">Q</font> ) )
 <b>by </b><i><a class="txt" href="aff_4.html#E1:29"><i><font color="Green" title="E24">A1</font></i></a>, <a class="txt" href="aff_4.html#E4:29"><i><font color="Green" title="E26">A3</font></i></a>, <a class="txt" href="aff_4.html#E8:29"><i><font color="Green" title="E29">A6</font></i></a>, <a class="txt" href="aff_4.html#E11:29"><i><font color="Green" title="E31">A8</font></i></a>, <a class="txt" href="aff_4.html#E13:29"><i><font color="Green" title="E32">A9</font></i></a>, <a class="txt" href="aff_4.html#E16:29"><i><font color="Green" title="E34">A11</font></i></a>, <a class="txt" href="aff_4.html#E18:29"><i><font color="Green" title="E36">A13</font></i></a>, <a class="txt" href="aff_4.html#E19:29"><i><font color="Green" title="E37">A14</font></i></a>, <a class="ref" href="aff_4.html#T18" target="_self" title="AFF_4:th.18">Th18</a></i>;<br/>


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