



 
Hi Kassandra, Is this the diagram you are describing? The circumference (perimeter) of a circle is 2 π r where r is the radius of the circle and π is approximately 3.1416. Thus the circumference of half a circle is π r units which for your circle is 4 π units. The remaining perimeter of the figure is made up of 4 line segments, each of length 4 units. Thus the perimeter of this figure is
I hope this helps,  


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