1.8 - Perimeter, Circumference, and Area

1.8 - Perimeter, Circumference, and Area

by Steve Dull

​Today's Objectives:

• ​To find perimeter or circumference of basic shapes

• ​To find area of basic shapes

​Important Terms

• ​The perimeter (P) of a polygon is the sum of the lengths of its sides

• ​The area (A) of a polygon is the number of square units it encloses.

​Formulas

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​Important!

​When measuring area, use square units such as square inches, square feet, square miles.

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​Circumference

​Tread carefully

​Be sure to make note of whether you are given radius or diameter in the problem - the circumference formula uses diameter so if you need the radius you'll have to double it.

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​We can also find area of figures with irregular shapes

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Let's try one...

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Poll

Select the image that best shows how well you think you understand area, perimeter, and circumference: