Geometry Filling In Missing Angles
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Not All There
Filling In Missing Angles

 

 Sometimes when we have crossed lines,

 we only get part of the drawing.
 Instead of something like this ...
 

 

 
 (the arrow heads mean that the lines are parallel)
 
 We might get:
 

 

 
 But don't get all excited.
 This is just the same old double cross lines.
 If you want to, you can put in more of the lines.
 Like:
 

 

 
 Example:
 Find angle X ...
 

 

 
 Step 1) 
 Put more of the lines in ...
 

 

 
 Step 2) 
 Put in all of the other 125 angles.
 

 

 
 Step 3) 
 Calculate the other angles ...
 

 A + B + 125 + 125 = 360

 A + B = 110

 A = B

 2A = 110

 A = 55     B = 55

 
 Step 4) 
 Put in the other angles ...
 

 

 
 So the measure of angle X is 55
 

   copyright 2005 Bruce Kirkpatrick

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