Perimeter 
        = 4a  | 
     
               Perimeter 
        = 2 กม pi กม r  | 
  
 
               Perimeter 
        = 2a + 2b  | 
     
               Perimeter 
        = 2a + 2b  | 
  
 
               Perimeter 
        = a + b + c  | 
     
               Perimeter 
        = a + b + c + d= 2m + c + d  | 
  
 
               Perimeter 
        = 4a  | 
     
               Perimeter 
        = ns, n = # of sides  | 
  
 
                 
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