| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elex |  |-  ( A e. LinesEE -> A e. _V ) | 
						
							| 2 |  | ovex |  |-  ( p Line q ) e. _V | 
						
							| 3 |  | eleq1 |  |-  ( A = ( p Line q ) -> ( A e. _V <-> ( p Line q ) e. _V ) ) | 
						
							| 4 | 2 3 | mpbiri |  |-  ( A = ( p Line q ) -> A e. _V ) | 
						
							| 5 | 4 | adantl |  |-  ( ( p =/= q /\ A = ( p Line q ) ) -> A e. _V ) | 
						
							| 6 | 5 | rexlimivw |  |-  ( E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) -> A e. _V ) | 
						
							| 7 | 6 | a1i |  |-  ( ( n e. NN /\ p e. ( EE ` n ) ) -> ( E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) -> A e. _V ) ) | 
						
							| 8 | 7 | rexlimivv |  |-  ( E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) -> A e. _V ) | 
						
							| 9 |  | eleq1 |  |-  ( x = A -> ( x e. LinesEE <-> A e. LinesEE ) ) | 
						
							| 10 |  | eqeq1 |  |-  ( x = A -> ( x = ( p Line q ) <-> A = ( p Line q ) ) ) | 
						
							| 11 | 10 | anbi2d |  |-  ( x = A -> ( ( p =/= q /\ x = ( p Line q ) ) <-> ( p =/= q /\ A = ( p Line q ) ) ) ) | 
						
							| 12 | 11 | rexbidv |  |-  ( x = A -> ( E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) <-> E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) ) ) | 
						
							| 13 | 12 | 2rexbidv |  |-  ( x = A -> ( E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) ) ) | 
						
							| 14 |  | df-lines2 |  |-  LinesEE = ran Line | 
						
							| 15 |  | df-line2 |  |-  Line = { <. <. p , q >. , x >. | E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } | 
						
							| 16 | 15 | rneqi |  |-  ran Line = ran { <. <. p , q >. , x >. | E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } | 
						
							| 17 |  | rnoprab |  |-  ran { <. <. p , q >. , x >. | E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } = { x | E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } | 
						
							| 18 | 14 16 17 | 3eqtri |  |-  LinesEE = { x | E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } | 
						
							| 19 | 18 | eleq2i |  |-  ( x e. LinesEE <-> x e. { x | E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } ) | 
						
							| 20 |  | abid |  |-  ( x e. { x | E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } <-> E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) | 
						
							| 21 |  | df-rex |  |-  ( E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) <-> E. n ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) ) | 
						
							| 22 | 21 | 2exbii |  |-  ( E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) <-> E. p E. q E. n ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) ) | 
						
							| 23 |  | exrot3 |  |-  ( E. n E. p E. q ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) <-> E. p E. q E. n ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 24 |  | r2ex |  |-  ( E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) <-> E. n E. p ( ( n e. NN /\ p e. ( EE ` n ) ) /\ E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) ) | 
						
							| 25 |  | r19.42v |  |-  ( E. q e. ( EE ` n ) ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) <-> ( ( n e. NN /\ p e. ( EE ` n ) ) /\ E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) ) | 
						
							| 26 |  | df-rex |  |-  ( E. q e. ( EE ` n ) ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) <-> E. q ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 27 | 25 26 | bitr3i |  |-  ( ( ( n e. NN /\ p e. ( EE ` n ) ) /\ E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) <-> E. q ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 28 | 27 | 2exbii |  |-  ( E. n E. p ( ( n e. NN /\ p e. ( EE ` n ) ) /\ E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) <-> E. n E. p E. q ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 29 | 24 28 | bitri |  |-  ( E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) <-> E. n E. p E. q ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 30 |  | anass |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) <-> ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 31 |  | anass |  |-  ( ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) /\ x = ( p Line q ) ) <-> ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) | 
						
							| 32 |  | simplrl |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> n e. NN ) | 
						
							| 33 |  | simplrr |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> p e. ( EE ` n ) ) | 
						
							| 34 |  | simpll |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> q e. ( EE ` n ) ) | 
						
							| 35 |  | simpr |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> p =/= q ) | 
						
							| 36 | 33 34 35 | 3jca |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) | 
						
							| 37 | 32 36 | jca |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) -> ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) ) | 
						
							| 38 |  | simpr2 |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> q e. ( EE ` n ) ) | 
						
							| 39 |  | simpl |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> n e. NN ) | 
						
							| 40 |  | simpr1 |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> p e. ( EE ` n ) ) | 
						
							| 41 | 38 39 40 | jca32 |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) ) | 
						
							| 42 |  | simpr3 |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> p =/= q ) | 
						
							| 43 | 41 42 | jca |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) ) | 
						
							| 44 | 37 43 | impbii |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) <-> ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) ) | 
						
							| 45 | 44 | anbi1i |  |-  ( ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ p =/= q ) /\ x = ( p Line q ) ) <-> ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = ( p Line q ) ) ) | 
						
							| 46 | 31 45 | bitr3i |  |-  ( ( ( q e. ( EE ` n ) /\ ( n e. NN /\ p e. ( EE ` n ) ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) <-> ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = ( p Line q ) ) ) | 
						
							| 47 | 30 46 | bitr3i |  |-  ( ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) <-> ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = ( p Line q ) ) ) | 
						
							| 48 |  | fvline |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> ( p Line q ) = { x | x Colinear <. p , q >. } ) | 
						
							| 49 |  | opex |  |-  <. p , q >. e. _V | 
						
							| 50 |  | dfec2 |  |-  ( <. p , q >. e. _V -> [ <. p , q >. ] `' Colinear = { x | <. p , q >. `' Colinear x } ) | 
						
							| 51 | 49 50 | ax-mp |  |-  [ <. p , q >. ] `' Colinear = { x | <. p , q >. `' Colinear x } | 
						
							| 52 |  | vex |  |-  x e. _V | 
						
							| 53 | 49 52 | brcnv |  |-  ( <. p , q >. `' Colinear x <-> x Colinear <. p , q >. ) | 
						
							| 54 | 53 | abbii |  |-  { x | <. p , q >. `' Colinear x } = { x | x Colinear <. p , q >. } | 
						
							| 55 | 51 54 | eqtri |  |-  [ <. p , q >. ] `' Colinear = { x | x Colinear <. p , q >. } | 
						
							| 56 | 48 55 | eqtr4di |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> ( p Line q ) = [ <. p , q >. ] `' Colinear ) | 
						
							| 57 | 56 | eqeq2d |  |-  ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) -> ( x = ( p Line q ) <-> x = [ <. p , q >. ] `' Colinear ) ) | 
						
							| 58 | 57 | pm5.32i |  |-  ( ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = ( p Line q ) ) <-> ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = [ <. p , q >. ] `' Colinear ) ) | 
						
							| 59 |  | anass |  |-  ( ( ( n e. NN /\ ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) ) /\ x = [ <. p , q >. ] `' Colinear ) <-> ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) ) | 
						
							| 60 | 47 58 59 | 3bitrri |  |-  ( ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) <-> ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 61 | 60 | 3exbii |  |-  ( E. p E. q E. n ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) <-> E. p E. q E. n ( q e. ( EE ` n ) /\ ( ( n e. NN /\ p e. ( EE ` n ) ) /\ ( p =/= q /\ x = ( p Line q ) ) ) ) ) | 
						
							| 62 | 23 29 61 | 3bitr4ri |  |-  ( E. p E. q E. n ( n e. NN /\ ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) ) <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) | 
						
							| 63 | 22 62 | bitri |  |-  ( E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) | 
						
							| 64 | 20 63 | bitri |  |-  ( x e. { x | E. p E. q E. n e. NN ( ( p e. ( EE ` n ) /\ q e. ( EE ` n ) /\ p =/= q ) /\ x = [ <. p , q >. ] `' Colinear ) } <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) | 
						
							| 65 | 19 64 | bitri |  |-  ( x e. LinesEE <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ x = ( p Line q ) ) ) | 
						
							| 66 | 9 13 65 | vtoclbg |  |-  ( A e. _V -> ( A e. LinesEE <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) ) ) | 
						
							| 67 | 1 8 66 | pm5.21nii |  |-  ( A e. LinesEE <-> E. n e. NN E. p e. ( EE ` n ) E. q e. ( EE ` n ) ( p =/= q /\ A = ( p Line q ) ) ) |