Geometry Large Degree Measure
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Round and Round
Large Degree Measure

 

 Place one ray at 3 O'clock.

 Place the other ray at 3 O'clock.
 

 

 
 How many degrees is this angle?
 
 Is it zero degrees?
 Or did we go all the way around the circle
 

 

 
 for an angle of 360 degrees?
 
 Big problem, eh?
 
 Well, not really.
 
 If you saw a 360 degree angle
 and a zero degree angle
 they would both look the same.
 
 So we just say:

 0 degrees = 360 degrees

 
 What happens if the angle goes 
 all the way around the circle twice?
 

 

 

 360 degrees + 360 degrees = 720 degrees

 
 But hey! We're right back where we started from.
 That means:

 0 degrees = 360 degrees = 720 degrees

 
 Here's the deal.
 Take any angle, add 360 degrees to it.
 What you get is equal to what you started with!
 
 This works with any angle, 
 not just 0 or 360 ...
 
 Say you have a 90 degree angle:
 

 

 
 add one trip around the circle (360 degrees) to it ...
 

 

 

90 degrees + 360 degrees = 450 degrees

 
 But you are right back where you started, so ...
 

450 degrees = 90 degrees

 

   copyright 2005 Bruce Kirkpatrick

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