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Step * of Lemma colinear-preserves-parallel

∀e:EuclideanPlane. ∀a,b,c,d,y:Point.  ((geo-parallel(e;a;b;c;d) ∧ Colinear(c;d;y) ∧ c ≠ y) ⇒ geo-parallel(e;a;b;c;y))
BY
{ (Auto THEN (D 7 THEN ExRepD) THEN (D 0 THEN Auto) THEN InstHyp [⌜x⌝] (9)⋅ THEN Auto) }

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Latex:

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


By

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Latex:
(Auto  THEN  (D  7  THEN  ExRepD)  THEN  (D  0  THEN  Auto)  THEN  InstHyp  [\mkleeneopen{}x\mkleeneclose{}]  (9)\mcdot{}  THEN  Auto)

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