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Step * of Lemma left-between-implies-right1

∀g:OrientedPlane. ∀a,b,x,y:Point.  (x leftof ab ⇒ x_b_y ⇒ y ≠ b ⇒ y leftof ba)
BY
{ (Auto THEN (InstLemma `lsep-opposite-iff` [⌜g⌝;⌜a⌝;⌜b⌝;⌜x⌝;⌜y⌝]⋅ THENA Auto)) }

1
1. g : OrientedPlane
2. a : Point
3. b : Point
4. x : Point
5. y : Point
6. x leftof ab
7. x_b_y
8. y ≠ b
9. ∃z:Point. (x_z_y ∧ Colinear(z;a;b)) ⇐⇒ x leftof ab ⇐⇒ y leftof ba
⊢ y leftof ba

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Latex:

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Latex:
\mforall{}g:OrientedPlane.  \mforall{}a,b,x,y:Point.    (x  leftof  ab  {}\mRightarrow{}  x\_b\_y  {}\mRightarrow{}  y  \mneq{}  b  {}\mRightarrow{}  y  leftof  ba)


By

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Latex:
(Auto  THEN  (InstLemma  `lsep-opposite-iff`  [\mkleeneopen{}g\mkleeneclose{};\mkleeneopen{}a\mkleeneclose{};\mkleeneopen{}b\mkleeneclose{};\mkleeneopen{}x\mkleeneclose{};\mkleeneopen{}y\mkleeneclose{}]\mcdot{}  THENA  Auto))

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