1. Use the triangle interior angles sum to complete the following table.
   
   

   Polygon	Number of Sides	Number of Triangles	Sketch	Interior Angles Sum
   triangle	3	1		180°
   quadrilateral	4	2		2 × 180° = 360°
   pentagon
   hexagon
   heptagon
   decagon

2. Look for a pattern in your table. Use this pattern to determine the interior angles sum for
   
   
   1. a hectagon (a 100-sided polygon)
      
      
      
   2. a myriagon (a 10 000-sided polygon)
      
      
      
      
3. Determine an expression that will allow you to find the interior angles sum of
   an n-sided polygon.
   

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