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              The figure shows a 
				cyclic 
				quadrilateral ABCD. E, F, G, and H are the 
				incenters and ra, 
				rb, rc, and rd are the 
				inradii 
				of the triangles ABD, ABC, BCD and ACD respectively. Prove that 
				EFGH is a rectangle and ra + rc = rb 
				+ rd. 
				  
						
                
                
				
                
                
				 
  
  
  
  
  						
						
		 
  
                
				See solution below 						
               		  
						  												
		 
  
  						
  						                		  
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