:: AFF_3 semantic presentation

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES1 means :Def1: :: AFF_3:def 1
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11, b12 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b2 <> b1 & b2 <> b3 & b1 <> b3 & b4 in b1 & b5 in b1 & b6 in b1 & b4 in b2 & b7 in b2 & b8 in b2 & b4 in b3 & b9 in b3 & b10 in b3 & b4 <> b5 & b4 <> b7 & b4 <> b9 & b11 <> b12 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b5 <> b6 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 implies b5,b9 // b11,b12 );
end;

:: deftheorem Def1 defines satisfying_DES1 AFF_3:def 1 :
for b1 being AffinPlane holds
( b1 is satisfying_DES1 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12, b13 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b3 <> b2 & b3 <> b4 & b2 <> b4 & b5 in b2 & b6 in b2 & b7 in b2 & b5 in b3 & b8 in b3 & b9 in b3 & b5 in b4 & b10 in b4 & b11 in b4 & b5 <> b6 & b5 <> b8 & b5 <> b10 & b12 <> b13 & not LIN b8,b6,b10 & not LIN b9,b7,b11 & b6 <> b7 & LIN b8,b6,b12 & LIN b9,b7,b12 & LIN b8,b10,b13 & LIN b9,b11,b13 & b6,b10 // b7,b11 implies b6,b10 // b12,b13 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES1 for satisfying_DES1 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES1_1 means :Def2: :: AFF_3:def 2
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11, b12 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b2 <> b1 & b2 <> b3 & b1 <> b3 & b4 in b1 & b5 in b1 & b6 in b1 & b4 in b2 & b7 in b2 & b8 in b2 & b4 in b3 & b9 in b3 & b10 in b3 & b4 <> b5 & b4 <> b7 & b4 <> b9 & b11 <> b12 & b9 <> b12 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b11,b12 implies b5,b9 // b6,b10 );
end;

:: deftheorem Def2 defines satisfying_DES1_1 AFF_3:def 2 :
for b1 being AffinPlane holds
( b1 is satisfying_DES1_1 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12, b13 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b3 <> b2 & b3 <> b4 & b2 <> b4 & b5 in b2 & b6 in b2 & b7 in b2 & b5 in b3 & b8 in b3 & b9 in b3 & b5 in b4 & b10 in b4 & b11 in b4 & b5 <> b6 & b5 <> b8 & b5 <> b10 & b12 <> b13 & b10 <> b13 & not LIN b8,b6,b10 & not LIN b9,b7,b11 & LIN b8,b6,b12 & LIN b9,b7,b12 & LIN b8,b10,b13 & LIN b9,b11,b13 & b6,b10 // b12,b13 implies b6,b10 // b7,b11 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES1_1 for satisfying_DES1_1 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES1_2 means :Def3: :: AFF_3:def 3
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11, b12 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b2 <> b1 & b2 <> b3 & b1 <> b3 & b4 in b1 & b5 in b1 & b6 in b1 & b4 in b2 & b7 in b2 & b8 in b2 & b9 in b3 & b10 in b3 & b4 <> b5 & b4 <> b7 & b4 <> b9 & b11 <> b12 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b9 <> b10 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 & b5,b9 // b11,b12 implies b4 in b3 );
end;

:: deftheorem Def3 defines satisfying_DES1_2 AFF_3:def 3 :
for b1 being AffinPlane holds
( b1 is satisfying_DES1_2 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12, b13 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b3 <> b2 & b3 <> b4 & b2 <> b4 & b5 in b2 & b6 in b2 & b7 in b2 & b5 in b3 & b8 in b3 & b9 in b3 & b10 in b4 & b11 in b4 & b5 <> b6 & b5 <> b8 & b5 <> b10 & b12 <> b13 & not LIN b8,b6,b10 & not LIN b9,b7,b11 & b10 <> b11 & LIN b8,b6,b12 & LIN b9,b7,b12 & LIN b8,b10,b13 & LIN b9,b11,b13 & b6,b10 // b7,b11 & b6,b10 // b12,b13 implies b5 in b4 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES1_2 for satisfying_DES1_2 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES1_3 means :Def4: :: AFF_3:def 4
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11, b12 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b2 <> b1 & b2 <> b3 & b1 <> b3 & b4 in b1 & b5 in b1 & b6 in b1 & b7 in b2 & b8 in b2 & b4 in b3 & b9 in b3 & b10 in b3 & b4 <> b5 & b4 <> b7 & b4 <> b9 & b11 <> b12 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b7 <> b8 & b5 <> b6 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 & b5,b9 // b11,b12 implies b4 in b2 );
end;

:: deftheorem Def4 defines satisfying_DES1_3 AFF_3:def 4 :
for b1 being AffinPlane holds
( b1 is satisfying_DES1_3 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12, b13 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b3 <> b2 & b3 <> b4 & b2 <> b4 & b5 in b2 & b6 in b2 & b7 in b2 & b8 in b3 & b9 in b3 & b5 in b4 & b10 in b4 & b11 in b4 & b5 <> b6 & b5 <> b8 & b5 <> b10 & b12 <> b13 & not LIN b8,b6,b10 & not LIN b9,b7,b11 & b8 <> b9 & b6 <> b7 & LIN b8,b6,b12 & LIN b9,b7,b12 & LIN b8,b10,b13 & LIN b9,b11,b13 & b6,b10 // b7,b11 & b6,b10 // b12,b13 implies b5 in b3 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES1_3 for satisfying_DES1_3 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES2 means :Def5: :: AFF_3:def 5
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b1 <> b2 & b1 <> b3 & b2 <> b3 & b4 in b1 & b5 in b1 & b6 in b2 & b7 in b2 & b8 in b3 & b9 in b3 & b1 // b2 & b1 // b3 & not LIN b6,b4,b8 & not LIN b7,b5,b9 & b10 <> b11 & b4 <> b5 & LIN b6,b4,b10 & LIN b7,b5,b10 & LIN b6,b8,b11 & LIN b7,b9,b11 & b4,b8 // b5,b9 implies b4,b8 // b10,b11 );
end;

:: deftheorem Def5 defines satisfying_DES2 AFF_3:def 5 :
for b1 being AffinPlane holds
( b1 is satisfying_DES2 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b2 <> b3 & b2 <> b4 & b3 <> b4 & b5 in b2 & b6 in b2 & b7 in b3 & b8 in b3 & b9 in b4 & b10 in b4 & b2 // b3 & b2 // b4 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b11 <> b12 & b5 <> b6 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 implies b5,b9 // b11,b12 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES2 for satisfying_DES2 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES2_1 means :Def6: :: AFF_3:def 6
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b1 <> b2 & b1 <> b3 & b2 <> b3 & b4 in b1 & b5 in b1 & b6 in b2 & b7 in b2 & b8 in b3 & b9 in b3 & b1 // b2 & b1 // b3 & not LIN b6,b4,b8 & not LIN b7,b5,b9 & b10 <> b11 & LIN b6,b4,b10 & LIN b7,b5,b10 & LIN b6,b8,b11 & LIN b7,b9,b11 & b4,b8 // b10,b11 implies b4,b8 // b5,b9 );
end;

:: deftheorem Def6 defines satisfying_DES2_1 AFF_3:def 6 :
for b1 being AffinPlane holds
( b1 is satisfying_DES2_1 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b2 <> b3 & b2 <> b4 & b3 <> b4 & b5 in b2 & b6 in b2 & b7 in b3 & b8 in b3 & b9 in b4 & b10 in b4 & b2 // b3 & b2 // b4 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b11 <> b12 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b11,b12 implies b5,b9 // b6,b10 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES2_1 for satisfying_DES2_1 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES2_2 means :Def7: :: AFF_3:def 7
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b1 <> b2 & b1 <> b3 & b2 <> b3 & b4 in b1 & b5 in b1 & b6 in b2 & b7 in b2 & b8 in b3 & b9 in b3 & b1 // b3 & not LIN b6,b4,b8 & not LIN b7,b5,b9 & b10 <> b11 & b4 <> b5 & LIN b6,b4,b10 & LIN b7,b5,b10 & LIN b6,b8,b11 & LIN b7,b9,b11 & b4,b8 // b5,b9 & b4,b8 // b10,b11 implies b1 // b2 );
end;

:: deftheorem Def7 defines satisfying_DES2_2 AFF_3:def 7 :
for b1 being AffinPlane holds
( b1 is satisfying_DES2_2 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b2 <> b3 & b2 <> b4 & b3 <> b4 & b5 in b2 & b6 in b2 & b7 in b3 & b8 in b3 & b9 in b4 & b10 in b4 & b2 // b4 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b11 <> b12 & b5 <> b6 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 & b5,b9 // b11,b12 implies b2 // b3 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES2_2 for satisfying_DES2_2 c1;
end;

definition
let c1 be AffinPlane;
attr a1 is satisfying_DES2_3 means :Def8: :: AFF_3:def 8
for b1, b2, b3 being Subset of a1
for b4, b5, b6, b7, b8, b9, b10, b11 being Element of a1 holds
( b1 is_line & b2 is_line & b3 is_line & b1 <> b2 & b1 <> b3 & b2 <> b3 & b4 in b1 & b5 in b1 & b6 in b2 & b7 in b2 & b8 in b3 & b9 in b3 & b1 // b2 & not LIN b6,b4,b8 & not LIN b7,b5,b9 & b10 <> b11 & b8 <> b9 & LIN b6,b4,b10 & LIN b7,b5,b10 & LIN b6,b8,b11 & LIN b7,b9,b11 & b4,b8 // b5,b9 & b4,b8 // b10,b11 implies b1 // b3 );
end;

:: deftheorem Def8 defines satisfying_DES2_3 AFF_3:def 8 :
for b1 being AffinPlane holds
( b1 is satisfying_DES2_3 iff for b2, b3, b4 being Subset of b1
for b5, b6, b7, b8, b9, b10, b11, b12 being Element of b1 holds
( b2 is_line & b3 is_line & b4 is_line & b2 <> b3 & b2 <> b4 & b3 <> b4 & b5 in b2 & b6 in b2 & b7 in b3 & b8 in b3 & b9 in b4 & b10 in b4 & b2 // b3 & not LIN b7,b5,b9 & not LIN b8,b6,b10 & b11 <> b12 & b9 <> b10 & LIN b7,b5,b11 & LIN b8,b6,b11 & LIN b7,b9,b12 & LIN b8,b10,b12 & b5,b9 // b6,b10 & b5,b9 // b11,b12 implies b2 // b4 ) );

notation
let c1 be AffinPlane;
synonym c1 satisfies_DES2_3 for satisfying_DES2_3 c1;
end;

theorem Th1: :: AFF_3:1
canceled;

theorem Th2: :: AFF_3:2
canceled;

theorem Th3: :: AFF_3:3
canceled;

theorem Th4: :: AFF_3:4
canceled;

theorem Th5: :: AFF_3:5
canceled;

theorem Th6: :: AFF_3:6
canceled;

theorem Th7: :: AFF_3:7
canceled;

theorem Th8: :: AFF_3:8
canceled;

theorem Th9: :: AFF_3:9
for b1 being AffinPlane holds
( b1 satisfies_DES1 implies b1 satisfies_DES1_1 )
proof
let c1 be AffinPlane;
assume E9: c1 satisfies_DES1 ;
let c2 be Subset of c1; :: according to AFF_3:def 2
let c3, c4 be Subset of c1;
let c5, c6, c7, c8, c9, c10, c11, c12, c13 be Element of c1;
assume that
E10: ( c2 is_line & c3 is_line & c4 is_line ) and
E11: ( c3 <> c2 & c3 <> c4 & c2 <> c4 ) and
E12: ( c5 in c2 & c6 in c2 & c7 in c2 & c5 in c3 & c8 in c3 & c9 in c3 & c5 in c4 & c10 in c4 & c11 in c4 & c5 <> c6 & c5 <> c8 & c5 <> c10 & c12 <> c13 & c10 <> c13 & not LIN c8,c6,c10 & not LIN c9,c7,c11 ) and
E13: ( LIN c8,c6,c12 & LIN c9,c7,c12 & LIN c8,c10,c13 & LIN c9,c11,c13 & c6,c10 // c12,c13 ) ;
set c14 = Line c8,c6;
set c15 = Line c8,c10;
( c8 <> c6 & c8 <> c10 & c6 <> c10 ) by E12, AFF_1:16;
then E14: ( Line c8,c6 is_line & Line c8,c10 is_line & c8 in Line c8,c6 & c6 in Line c8,c6 & c8 in Line c8,c10 & c10 in Line c8,c10 & c12 in Line c8,c6 & c13 in Line c8,c10 ) by E13, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
E15: ( c7 <> c9 & c9 <> c11 & c7 <> c11 ) by E12, AFF_1:16;
E16: ( Line c8,c10 <> c3 & Line c8,c6 <> c3 ) by E10, E11, E12, E14, AFF_1:30;
E17: ( c8 <> c5 & c8 <> c6 & c8 <> c10 ) by E12, AFF_1:16;
E18: Line c8,c6 <> Line c8,c10 by E12, E14, AFF_1:33;
E19: not LIN c5,c6,c10
proof
assume LIN c5,c6,c10 ;
then c10 in c2 by E10, E12, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
c12 <> c8 by E12, E13, AFF_1:69;
then E20: c12 <> c9 by E10, E12, E14, E16, AFF_1:30;
c13 <> c8
proof
assume E21: c13 = c8 ;
( not LIN c8,c10,c6 & c10,c6 // c13,c12 & LIN c8,c10,c13 & LIN c8,c6,c12 ) by E12, E13, AFF_1:13, AFF_1:15;
hence not verum by E12, E21, AFF_1:69;
end;
then E21: c13 <> c9 by E10, E12, E14, E16, AFF_1:30;
E22: not LIN c9,c12,c13
proof
assume LIN c9,c12,c13 ;
then E23: LIN c12,c13,c9 by AFF_1:15;
set c16 = Line c12,c13;
E24: ( Line c12,c13 is_line & c12 in Line c12,c13 & c13 in Line c12,c13 & c9 in Line c12,c13 ) by E12, E23, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
( LIN c12,c9,c7 & LIN c13,c9,c11 ) by E13, AFF_1:15;
then ( c7 in Line c12,c13 & c11 in Line c12,c13 ) by E20, E21, E24, AFF_1:39;
hence not verum by E12, E24, AFF_1:33;
end;
E23: c6 <> c12 by E12, E13, AFF_1:23;
( LIN c5,c6,c7 & LIN c9,c12,c7 & LIN c5,c10,c11 & LIN c9,c13,c11 ) by E10, E12, E13, AFF_1:15, AFF_1:33;
hence c6,c10 // c7,c11 by E9, E10, E12, E13, E14, E15, E16, E17, E18, E19, E22, E23, Def1;
end;

theorem Th10: :: AFF_3:10
for b1 being AffinPlane holds
( b1 satisfies_DES1_1 implies b1 satisfies_DES1 )
proof
let c1 be AffinPlane;
assume E9: c1 satisfies_DES1_1 ;
let c2 be Subset of c1; :: according to AFF_3:def 1
let c3, c4 be Subset of c1;
let c5, c6, c7, c8, c9, c10, c11, c12, c13 be Element of c1;
assume that
E10: ( c2 is_line & c3 is_line & c4 is_line ) and
E11: ( c3 <> c2 & c3 <> c4 & c2 <> c4 ) and
E12: ( c5 in c2 & c6 in c2 & c7 in c2 & c5 in c3 & c8 in c3 & c9 in c3 & c5 in c4 & c10 in c4 & c11 in c4 & c5 <> c6 & c5 <> c8 & c5 <> c10 & c12 <> c13 & not LIN c8,c6,c10 & not LIN c9,c7,c11 & c6 <> c7 ) and
E13: ( LIN c8,c6,c12 & LIN c9,c7,c12 & LIN c8,c10,c13 & LIN c9,c11,c13 & c6,c10 // c7,c11 ) ;
set c14 = Line c8,c6;
set c15 = Line c8,c10;
( c8 <> c6 & c8 <> c10 & c6 <> c10 ) by E12, AFF_1:16;
then E14: ( Line c8,c6 is_line & Line c8,c10 is_line & c8 in Line c8,c6 & c6 in Line c8,c6 & c8 in Line c8,c10 & c10 in Line c8,c10 & c12 in Line c8,c6 & c13 in Line c8,c10 ) by E13, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
E15: ( c7 <> c9 & c9 <> c11 & c7 <> c11 ) by E12, AFF_1:16;
E16: Line c8,c6 <> c3 by E10, E11, E12, E14, AFF_1:30;
E17: Line c8,c10 <> c3 by E10, E11, E12, E14, AFF_1:30;
E18: ( Line c8,c10 <> c3 & Line c8,c6 <> c3 ) by E10, E11, E12, E14, AFF_1:30;
E19: ( c8 <> c5 & c8 <> c6 & c8 <> c10 ) by E12, AFF_1:16;
E20: Line c8,c6 <> Line c8,c10 by E12, E14, AFF_1:33;
E21: not LIN c5,c6,c10
proof
assume LIN c5,c6,c10 ;
then c10 in c2 by E10, E12, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
E22: c10 <> c11
proof
assume c10 = c11 ;
then ( c10,c6 // c10,c7 & LIN c5,c6,c7 & not LIN c5,c10,c6 ) by E10, E12, E13, E21, AFF_1:13, AFF_1:15, AFF_1:33;
hence not verum by E12, AFF_1:23;
end;
E23: now
assume E24: not LIN c9,c12,c13 ;
( LIN c5,c6,c7 & LIN c9,c12,c7 & LIN c5,c10,c11 & LIN c9,c13,c11 ) by E10, E12, E13, AFF_1:15, AFF_1:33;
hence c6,c10 // c12,c13 by E9, E10, E12, E13, E14, E15, E18, E19, E20, E21, E22, E24, Def2;
end;
now
assume E24: LIN c9,c12,c13 ;
set c16 = Line c9,c7;
set c17 = Line c9,c11;
E25: LIN c9,c13,c12 by E24, AFF_1:15;
E26: ( Line c9,c7 is_line & Line c9,c11 is_line & c9 in Line c9,c7 & c7 in Line c9,c7 & c12 in Line c9,c7 & c9 in Line c9,c11 & c11 in Line c9,c11 & c13 in Line c9,c11 ) by E13, E15, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
then E27: Line c9,c7 <> Line c9,c11 by E12, AFF_1:33;
E28: now
assume c9 <> c12 ;
then E29: c13 in Line c9,c7 by E24, E26, AFF_1:39;
then E30: c13 = c9 by E26, E27, AFF_1:30;
LIN c8,c10,c9 by E13, E26, E27, E29, AFF_1:30;
then c9 in Line c8,c10 by AFF_1:def 2;
then E31: c8 = c9 by E10, E12, E14, E17, AFF_1:30;
Line c9,c7 <> Line c8,c6
proof
assume Line c9,c7 = Line c8,c6 ;
then LIN c6,c7,c8 by E14, E26, AFF_1:33;
then c8 in c2 by E10, E12, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
then c12 = c13 by E14, E26, E30, E31, AFF_1:30;
hence c6,c10 // c12,c13 by AFF_1:12;
end;
now
assume c9 <> c13 ;
then E29: c12 in Line c9,c11 by E25, E26, AFF_1:39;
then E30: c12 = c9 by E26, E27, AFF_1:30;
LIN c8,c6,c9 by E13, E26, E27, E29, AFF_1:30;
then c9 in Line c8,c6 by AFF_1:def 2;
then E31: c8 = c9 by E10, E12, E14, E16, AFF_1:30;
Line c9,c11 <> Line c8,c10
proof
assume Line c9,c11 = Line c8,c10 ;
then LIN c10,c11,c8 by E14, E26, AFF_1:33;
then c8 in c4 by E10, E12, E22, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
then c12 = c13 by E14, E26, E30, E31, AFF_1:30;
hence c6,c10 // c12,c13 by AFF_1:12;
end;
hence c6,c10 // c12,c13 by E12, E28;
end;
hence c6,c10 // c12,c13 by E23;
end;

theorem Th11: :: AFF_3:11
for b1 being AffinPlane holds
( b1 satisfies_DES implies b1 satisfies_DES1 )
proof
let c1 be AffinPlane;
assume E9: c1 satisfies_DES ;
let c2 be Subset of c1; :: according to AFF_3:def 1
let c3, c4 be Subset of c1;
let c5, c6, c7, c8, c9, c10, c11, c12, c13 be Element of c1;
assume that
E10: ( c2 is_line & c3 is_line & c4 is_line ) and
E11: ( c3 <> c2 & c3 <> c4 & c2 <> c4 ) and
E12: ( c5 in c2 & c6 in c2 & c7 in c2 & c5 in c3 & c8 in c3 & c9 in c3 & c5 in c4 & c10 in c4 & c11 in c4 & c5 <> c6 & c5 <> c8 & c5 <> c10 & c12 <> c13 & not LIN c8,c6,c10 & not LIN c9,c7,c11 & c6 <> c7 ) and
E13: ( LIN c8,c6,c12 & LIN c9,c7,c12 & LIN c8,c10,c13 & LIN c9,c11,c13 & c6,c10 // c7,c11 ) ;
set c14 = Line c9,c7;
set c15 = Line c9,c11;
E14: ( c6 <> c8 & c6 <> c10 & c8 <> c10 & c7 <> c9 & c7 <> c11 & c9 <> c11 ) by E12, AFF_1:16;
then E15: ( Line c9,c7 is_line & Line c9,c11 is_line & c9 in Line c9,c7 & c7 in Line c9,c7 & c12 in Line c9,c7 & c9 in Line c9,c11 & c11 in Line c9,c11 & c13 in Line c9,c11 ) by E13, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
E16: not LIN c5,c6,c10
proof
assume LIN c5,c6,c10 ;
then c10 in c2 by E10, E12, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
E17: c5 <> c7
proof
assume E18: c5 = c7 ;
( LIN c5,c6,c7 & LIN c5,c10,c11 ) by E10, E12, AFF_1:33;
hence not verum by E13, E14, E16, E18, AFF_1:69;
end;
E18: c5 <> c11
proof
assume E19: c5 = c11 ;
( LIN c5,c6,c7 & LIN c5,c10,c11 & c10,c6 // c11,c7 & not LIN c5,c10,c6 ) by E10, E12, E13, E16, AFF_1:13, AFF_1:15, AFF_1:33;
hence not verum by E17, E19, AFF_1:69;
end;
E19: c10 <> c11
proof
assume c10 = c11 ;
then ( LIN c5,c6,c7 & c10,c6 // c10,c7 & not LIN c5,c10,c6 ) by E10, E12, E13, E16, AFF_1:13, AFF_1:15, AFF_1:33;
hence not verum by E12, AFF_1:23;
end;
E20: ( Line c9,c7 <> c3 & Line c9,c11 <> c3 & Line c9,c7 <> Line c9,c11 ) by E10, E11, E12, E15, E17, E18, AFF_1:30, AFF_1:33;
set c16 = Line c8,c10;
E21: ( Line c8,c10 is_line & c8 in Line c8,c10 & c10 in Line c8,c10 & c13 in Line c8,c10 ) by E13, E14, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
then consider c17 being Subset of c1 such that
E22: ( c11 in c17 & Line c8,c10 // c17 ) by AFF_1:63;
E23: ( c17 is_line & c17 // Line c8,c10 ) by E22, AFF_1:50;
not c17 // c3
proof
assume c17 // c3 ;
then Line c8,c10 // c3 by E22, AFF_1:58;
then c10 in c3 by E12, E21, AFF_1:59;
hence not verum by E10, E11, E12, AFF_1:30;
end;
then consider c18 being Element of c1 such that
E24: ( c18 in c17 & c18 in c3 ) by E10, E23, AFF_1:72;
E25: c18 <> c9
proof
assume c18 = c9 ;
then Line c9,c11 = c17 by E14, E15, E22, E23, E24, AFF_1:30;
then Line c8,c10 = Line c9,c11 by E15, E21, E22, AFF_1:59;
then LIN c10,c11,c8 by E15, E21, AFF_1:33;
then c8 in c4 by E10, E12, E19, AFF_1:39;
hence not verum by E10, E11, E12, AFF_1:30;
end;
( c10,c8 // c11,c18 & c10,c6 // c11,c7 ) by E13, E21, E22, E24, AFF_1:13, AFF_1:53;
then E26: c8,c6 // c18,c7 by E9, E10, E11, E12, E24, AFF_2:def 4;
c8,c6 // c8,c12 by E13, AFF_1:def 1;
then ( c18,c7 // c8,c12 & c8,c13 // c18,c11 ) by E14, E21, E22, E24, E26, AFF_1:14, AFF_1:53;
then ( c18,c7 // c8,c12 & c18,c11 // c8,c13 ) by AFF_1:13;
then c7,c11 // c12,c13 by E9, E10, E12, E14, E15, E20, E24, E25, AFF_2:def 4;
hence c6,c10 // c12,c13 by E13, E14, AFF_1:14;
end;

theorem Th12: :: AFF_3:12
for b1 being AffinPlane holds
( b1 satisfies_DES implies b1 satisfies_DES1_2 )
proof
let c1 be AffinPlane;
assume E9: c1 satisfies_DES ;
then E10: c1 satisfies_DES_1 by AFF_2:16;
let c2 be Subset of c1; :: according to AFF_3:def 3
let c3, c4 be Subset of c1;
let c5, c6, c7, c8, c9, c10, c11, c12, c13 be Element of c1;
assume that
E11: ( c2 is_line & c3 is_line & c4 is_line ) and
E12: ( c3 <> c2 & c3 <> c4 & c2 <> c4 ) and
E13: ( c5 in c2 & c6 in c2 & c7 in c2 & c5 in c3 & c8 in c3 & c9 in c3 & c10 in c4 & c11 in c4 & c5 <> c6 & c5 <> c8 & c5 <> c10 & c12 <> c13 & not LIN c8,c6,c10 & not LIN c9,c7,c11 & c10 <> c11 ) and
E14: ( LIN c8,c6,c12 & LIN c9,c7,c12 & LIN c8,c10,c13 & LIN c9,c11,c13 & c6,c10 // c7,c11 & c6,c10 // c12,c13 ) ;
E15: ( c6 <> c8 & c6 <> c10 & c8 <> c10 & c7 <> c9 & c7 <> c11 & c9 <> c11 ) by E13, AFF_1:16;
E16: ( c9 <> c7 & c9 <> c11 ) by E13, AFF_1:16;
set c14 = Line c9,c7;
set c15 = Line c9,c11;
E17: ( Line c9,c7 is_line & Line c9,c11 is_line & c9 in Line c9,c7 & c7 in Line c9,c7 & c12 in Line c9,c7 & c9 in Line c9,c11 & c11 in Line c9,c11 & c13 in Line c9,c11 ) by E14, E15, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
then E18: Line c9,c7 <> Line c9,c11 by E13, AFF_1:33;
E19: c8 <> c13
proof
assume E20: c8 = c13 ;
( not LIN c8,c10,c6 & c10,c6 // c13,c12 ) by E13, E14, AFF_1:13, AFF_1:15;
hence not verum by E13, E14, E20, AFF_1:69;
end;
E20: c9 <> c13
proof
assume E21: c9 = c13 ;
c7,c11 // c12,c13 by E14, E15, AFF_1:14;
then ( c11,c7 // c13,c12 & not LIN c9,c11,c7 ) by E13, AFF_1:13, AFF_1:15;
hence not verum by E13, E14, E21, AFF_1:69;
end;
E21: c9 <> c12
proof
assume E22: c9 = c12 ;
c7,c11 // c12,c13 by E14, E15, AFF_1:14;
hence not verum by E13, E14, E22, AFF_1:69;
end;
E22: c8 <> c12 by E13, E14, AFF_1:69;
now
E23: now
assume E24: Line c9,c11 = c3 ;
LIN c8,c13,c10 by E14, AFF_1:15;
then c10 in c3 by E13, E17, E19, E24, AFF_1:39;
then c3 = Line c10,c11 by E13, E17, E24, AFF_1:71;
hence c5 in c4 by E11, E13, AFF_1:71;
end;
now
assume E24: Line c9,c11 <> c3 ;
set c16 = Line c8,c10;
E25: ( Line c8,c10 is_line & c8 in Line c8,c10 & c10 in Line c8,c10 & c13 in Line c8,c10 ) by E14, E15, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
then consider c17 being Subset of c1 such that
E26: ( c11 in c17 & Line c8,c10 // c17 ) by AFF_1:63;
E27: c17 is_line by E26, AFF_1:50;
not c17 // c3
proof
assume c17 // c3 ;
then Line c8,c10 // c3 by E26, AFF_1:58;
then c13 in c3 by E13, E25, AFF_1:59;
hence not verum by E11, E13, E17, E20, E24, AFF_1:30;
end;
then consider c18 being Element of c1 such that
E28: ( c18 in c17 & c18 in c3 ) by E11, E27, AFF_1:72;
E29: ( c13,c8 // c11,c18 & c8,c10 // c18,c11 ) by E25, E26, E28, AFF_1:53;
then E30: ( c11,c18 // c13,c8 & c8,c10 // c18,c11 ) by AFF_1:13;
E31: c18 <> c9
proof
assume c18 = c9 ;
then Line c9,c11 = c17 by E15, E17, E26, E27, E28, AFF_1:30;
then Line c8,c10 = Line c9,c11 by E17, E25, E26, AFF_1:59;
then ( LIN c10,c11,c8 & LIN c10,c11,c9 ) by E17, E25, AFF_1:33;
then E32: ( c8 in c4 & c9 in c4 ) by E11, E13, AFF_1:39;
set c19 = Line c8,c6;
set c20 = Line c6,c10;
E33: ( Line c8,c6 is_line & c8 in Line c8,c6 & c6 in Line c8,c6 & c12 in Line c8,c6 ) by E14, E15, AFF_1:26, AFF_1:def 2, AFF_1:def 3;
E34: ( Line c6,c10 is_line & c6 in Line c6,c10 & c10 in Line c6,c10 ) by E15, AFF_1:26, AFF_1:def 3;
E35: c6 <> c7
proof
assume c6 = c7 ;
then LIN c6,c10,c11 by E14, AFF_1:def 1;
then c11 in Line c6,c10 by AFF_1:def 2;
then Line c6,c10 = c4 by E11, E13, E34, AFF_1:30;
hence not verum by E13, E32, E34, AFF_1:33;
end;
c8 <> c9
proof
assume E36: c8 = c9 ;
Line c9,c7 <> Line c8,c6
proof
assume Line c9,c7 = Line c8,c6 ;
then Line c8,c6 = c2 by E11, E13, E17, E33,