Definition: 6.03: Height of a Figure
(Definition 3 from Book 6 of Euclid's “Elements”)
The height of any figure is the (straight line) drawn from the vertex perpendicular to the base.
Modern Formulation
The height of a figure is the longest segment which can be drawn perpendicularly to the base.
Mentioned in:
Corollaries: 1
Proofs: 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
Propositions: 27 28 29 30 31 32 33 34 35 36 37 38 39 40
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016