let n be Element of NAT ; for x being Element of REAL n
for L being Element of line_of_REAL n st not x in L & L is being_line holds
ex P being Element of plane_of_REAL n st
( x in P & L c= P & P is being_plane )
let x be Element of REAL n; for L being Element of line_of_REAL n st not x in L & L is being_line holds
ex P being Element of plane_of_REAL n st
( x in P & L c= P & P is being_plane )
let L be Element of line_of_REAL n; ( not x in L & L is being_line implies ex P being Element of plane_of_REAL n st
( x in P & L c= P & P is being_plane ) )
consider P being Element of plane_of_REAL n such that
A1:
( x in P & L c= P )
by Th104;
assume
( not x in L & L is being_line )
; ex P being Element of plane_of_REAL n st
( x in P & L c= P & P is being_plane )
then consider x1, x2 being Element of REAL n such that
A2:
L = Line (x1,x2)
and
A3:
x - x1,x2 - x1 are_lindependent2
by Th60;
take
P
; ( x in P & L c= P & P is being_plane )
( x1 in L & x2 in L )
by A2, EUCLID_4:9;
then
P = plane (x1,x,x2)
by A1, A3, Th97;
hence
( x in P & L c= P & P is being_plane )
by A1, A3, Def10; verum