# How to Find the Area of an Octadecagon?

An octadecagon is an 18-sided polygon. The area of an octadecagon can be calculated by the equation for regular polygon area, which is 1/4 * number of sides * one side's measurement squared * cotan...
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http://www.ehow.com/how_8116130_area-octadecagon.html

## How to Find the Area of a Semicircle?

A semicircle is half a circle. They can appear on all types of math tests and in all types of math questions, and most of the time, the area will be very useful in solving a problem involving this ...
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http://www.wikihow.com/Find-the-Area-of-a-Semicircle

## How to Find the Area of a Roundabout?

A roundabout is a type of intersection that is circular in nature with an "island" of land in the middle. Roundabouts are supposed to increase traffic capacity when compared to traditional intersec...
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http://www.ehow.com/how_8390403_area-roundabout.html

## How to Find the Area of a Shape?

Here is how to calculate the area of a regular shape (square and rectangle only) and a irregular shape. 1. is the square and rectangle and 2. is the irregular

http://www.wikihow.com/Find-the-Area-of-a-Shape

## How to Find the Area of a Square?

Find the area of a square is a common math problem. Read on to learn how to do this.

http://www.wikihow.com/Find-the-Area-of-a-Square