Proposition: Prop. 11.12: Construction of Straight Line Perpendicular to Plane from point on Plane
Euclid's Formulation
To set up a straight line at right angles to a given plane from a given point in it.
* Let the given plane be the reference (plane), and $A$ a point in it.
* So, it is required to set up a straight line at right angles to the reference plane at point $A$.
Modern Formulation
(not yet contributed)
Table of Contents
Proofs: 1
Mentioned in:
Proofs: 1 2 3 4
Thank you to the contributors under CC BYSA 4.0!
 Github:

 nonGithub:
 @Fitzpatrick
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