“If you’re in a cold room, go stand in the corner. It’s 90 degrees” is a geometry joke that has been printed on many images. “Why do Aggies/blondes stand in the corner when they are cold? Because it’s 90 degrees there” was posted to the newsgroup alt.humor.puns on May 21, 1997.
 
   
Wikipedia: Right angle
In geometry and trigonometry, a right angle is an angle that bisects the angle formed by two adjacent parts of a straight line. More precisely, if a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. As a rotation, a right angle corresponds to a quarter turn (that is, a quarter of a full circle).
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A right angle is equal to 90 degrees.
 
Google Groups: alt.humor.puns
Aggie Joke
Maria ISO/son 10-19-71
5/21/97
Frank Reid wrote:
> > Richard Rendon ” says:
>
> > It seems that was a power outage recently in Aggieland…
> >
> > Five Aggies got stuck on an escalator and had to wait for the power to
> > come back on
> >
> Why do Aggies/blondes/

stand in the corner when they are cold?
> Because it’s 90 degrees there.
 
Twitter
ripperdoc
‏@ripperdoc
Cold? Go to the corner, it’s 90 degrees.
1:46 AM - 9 Mar 2009
 
Twitter
Madayar
‏@Madayar
“It’s so cold in my room!” - “Stand in the corner.” - “Why?” - “It’s always 90 degrees there.”
4:06 AM - 11 Mar 2009
 
Reddit
If you are ever cold, just stand in the corner. (self.Punny)
submitted September 6, 2013 by davie1985
Most corners are 90 degrees!
 
Reddit—Dad Jokes
Go stand in the corner. (self.dadjokes)
submitted January 29, 2014 by Wafflizer5000
My teacher dropped this one in math class today.
Girl: it’s so cold in here
Teacher: why don’t you go stand in the corner
Girl: [confused look] why?
Teacher: because it’s 90 degrees over there
 
Reddit
Why should you stand in a corner when you are cold?
submitted September 11, 2014 by MarcusCrown
Because corners are 90 degrees
 
Google Books
Book of Jokes
By Bouchaib Sidah
Lulu Publishing (Lulu.com)
2015
Pg. 49:
Son: Dad, it’s so cold in here!
Father: Go stand in the corner.
Son: Why? Father: The corner is 90 degrees.
 
Google Books
Clean Jokes
By Jeo King
Marine Publishing
2016
Pg. ?:
If you ever get cold, just stand in the corner of a room for a while. They’re normally around 90 degrees.
Anonymous
 
Twitter
Jen
‏@quipsNscribbles
If you’re ever in a cold room, just go stand in the corner. It’s 90 degrees! #ClassicJokeTuesday
9:55 AM - 8 Nov 2016