let FdSp be FanodesSp; :: thesis: for b, q, c, a, p, r being Element of FdSp st not b,q,c is_collinear & parallelogram a,p,b,q & parallelogram a,p,c,r holds
parallelogram b,q,c,r
let b, q, c, a, p, r be Element of FdSp; :: thesis: ( not b,q,c is_collinear & parallelogram a,p,b,q & parallelogram a,p,c,r implies parallelogram b,q,c,r )
assume
( not b,q,c is_collinear & parallelogram a,p,b,q & parallelogram a,p,c,r )
; :: thesis: parallelogram b,q,c,r
then
( not b,q,c is_collinear & a <> p & a,p '||' b,q & a,p '||' c,r & b,c '||' q,r )
by Def3, Th34, Th47;
then
( not b,q,c is_collinear & b,q '||' c,r & b,c '||' q,r )
by PARSP_1:def 12;
hence
parallelogram b,q,c,r
by Def3; :: thesis: verum