Talk:Right angle

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Mathematics rating:
C Class
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 Field: Geometry

Definition?[edit]

Please check the order of definition. Defining the right angle as 90° seems improper to me, as a degree is commonly described as 1/90 of a right angle, or 1/360 of a full rotation. If a full rotation is a basic notion, then the right angle would be more clearly derived from it than from a degree. It should be possibly noted also, what axiom states the full turn meaning, and the property 'all full turns are equal' so that we can derive 'all their quarters (ie. right angles) are equal'. --CiaPan 08:51, 2 November 2007 (UTC)

My Geometry textbook has a hole in the logic there, too. Zginder 2008-05-24T19:44Z (UTC)

its seiys head —Preceding unsigned comment added by 92.7.142.253 (talk) 17:24, 6 April 2011 (UTC)

Saving some speedy-reverted content[edit]

Saving some speedy-reverted content. Maybe could be reworked/reintroduced into the article.

Arc with dot symbol[edit]

A Polish colleague of mine uses the circle with dot notation, but I have not found any non-polish people who use it. Anyone found an authoritative source for this symbol? Billlion (talk) 21:44, 23 August 2013 (UTC)

In Germany, as to my knowledge, the circle with dot notation is actually the only one that is used, at least in school education. I only got to know the square notation when reading English publications in university (I am German myself). While I do not have any particular "authoritative source" for this symbol, any German elementary geometry school book should suffice. --89.204.130.83 (talk) 12:09, 1 September 2013 (UTC)