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Step * of Lemma geo-colinear-preserves-parallel

∀e:EuclideanPlane. ∀a,b,c,d,x:Point.
  (geo-parallel-points(e;a;b;c;d) ⇒ Colinear(a;b;x) ⇒ a ≠ x ⇒ geo-parallel-points(e;a;x;c;d))
BY
{ (((((Auto THEN D -3) THEN D 0) THEN D 0 THEN Auto) THEN D -4 THEN Auto)
   THEN ExRepD
   THEN InstConcl [⌜x@0⌝;⌜y⌝]⋅
   THEN Auto) }

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Latex:

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Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a,b,c,d,x:Point.
    (geo-parallel-points(e;a;b;c;d)  {}\mRightarrow{}  Colinear(a;b;x)  {}\mRightarrow{}  a  \mneq{}  x  {}\mRightarrow{}  geo-parallel-points(e;a;x;c;d))


By

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Latex:
(((((Auto  THEN  D  -3)  THEN  D  0)  THEN  D  0  THEN  Auto)  THEN  D  -4  THEN  Auto)
  THEN  ExRepD
  THEN  InstConcl  [\mkleeneopen{}x@0\mkleeneclose{};\mkleeneopen{}y\mkleeneclose{}]\mcdot{}
  THEN  Auto)

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