Polygon Island

In this trip don't get lossed in the shapes, knowing the area of these shaped confusing islands will help you travel from one to another.

Areas of Polygons and Circles

Polygons

The first thing we need to know is that the area of a shape is a number that tells how many square units are needed to cover the shape. Area can be measured in different units, such as square feet, square meters, or square inches.


One way you  can find an area is by drawing a shape on graph paper, and counting the squares inside the shape.

But we a more practicle way is to use area formulas instead. Note that every polygon and circle  has a formula for finding its area.

Area of a Rectangle

A rectangle is a great, easy shape to begin with. The area of a rectangle is equal to the product of the length of its base and the length of its height. The height is perpendicular to the base.

A=bh

Sometimes the base may be called the width(w) A=wh



 

Area of a Parallelogram

A=bh

To find the area of a parallelogram, we can use the same formula that we used for the area of a rectangle, multiplying the length of the base times the length of the height.

Area of a Square
A=s2

A square is a special rectangle, and you can find its area using the rectangle formula. However, since the base and height are always the same number for a square, we usually call them "sides." The area of a square is equal to the length of one side squared.

Area of a Triangle

A=1/2bh


Other polygon formulas

Area of a Trapezoid



 Circle

Area of a Circle

 

Now lets put what we have learned to use

Area of rectangle with base = 14 cm and height = 7 cm 

Area of triangle with base = 4 cm and height = 6 cm

Area of parallelogram with base = 15 ft and height = 5 ft

Area of trapezoid with height = 10 cm, bases = 7 cm and 15 cm

Area of a circle with diameter = 10 cm