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# At a Glance - Area Formulas

Let's go over these formulas one more time.

Formulas for different shapes:

## Area of Circle = πr2

#### Area of a Regular Polygon

a = apothem

P =  perimeter

 This is a regular hexagon with sides of 3.4 cm and an apothem of 2.9 cm. This is a regular quadrilateral, or square, with sides of 4.4 cm and an apothem of 2.2 cm. You can compare this to multiplying base times height:

#### Exercise 1

Find the area of a circle with a diameter of 3 inches.

#### Exercise 2

Find the area of:

#### Exercise 3

Find the area of:

#### Exercise 4

This isosceles right triangle: