Finding Perimeter and CircumferencePerimeterThe perimeter of a geometrical figure is the complete distance around that figure. To find the perimeter, simply add up the lengths of the figure's sides. Example: What is the perimeter of a rectangle that measures 3 inches by 8 inches?
Example: What is the perimeter of a pentagon in which each side measures 4 inches?
Example: What is the perimeter of a triangle that has sides measuring 12 inches, 9 inches, and 6 inches?
CircumferenceThe circumference of a circle—the complete distance around a circle—can be found by using this formula: C = π2r, in which π is about 3.1416 and r is the radius.
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