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Step * 1 of Lemma geo-add-length-cancel-left-lt2


1. e : BasicGeometry
2. y : Length
3. z : Length
4. z < z + y
⊢ 0 < y
BY
{ (InstLemma `geo-add-length-cancel-left-lt` [⌜e⌝;⌜0⌝;⌜y⌝;⌜z⌝]⋅ THEN Auto THEN Unfold `geo-zero-length` 0 THEN Auto) }

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Latex:

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Latex:

1.  e  :  BasicGeometry
2.  y  :  Length
3.  z  :  Length
4.  z  <  z  +  y
\mvdash{}  0  <  y


By

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Latex:
(InstLemma  `geo-add-length-cancel-left-lt`  [\mkleeneopen{}e\mkleeneclose{};\mkleeneopen{}0\mkleeneclose{};\mkleeneopen{}y\mkleeneclose{};\mkleeneopen{}z\mkleeneclose{}]\mcdot{}
  THEN  Auto
  THEN  Unfold  `geo-zero-length`  0
  THEN  Auto)

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