Question 287332:  what is the smallest number of acute angles in any triangle? Explain. 
 Answer by Deina(147)      (Show Source): 
You can  put this solution on YOUR website! Given that the inside angles of a standard 2 dimensional triangle equal 180 degrees, and the smallest non-acute angle is 90 degrees, at least two of those 3 inside angles must be < 90 degrees, thus acute.
  
OTOH, a triangle over a sphere need have zero acute angles, an example would be the triangle of Tokyo, Los Angeles, London.  
A triangle drawn encompassing a corner of a cubeoid shape would have 3 90 degree angles.  
Do not use this as the answer on a test without discussing it with your instructor first! 
And bob's your uncle! 
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