Polygon Facts

The secret to performing well in any competitive examination is the ability to recall facts about topics and applying those facts to solve both simple and challenging questions. I will teach you the polygon facts and tricks you need to score higher marks in your WASSCE and other competitive exams.

Fact 1:

The sum of the exterior angles of any polygon is 3600

This is true whether the polygon is regular or not.

Worked Example 1

Four of the exterior angles of a pentagon are the same. The fifth angle is 60°. Calculate the size of one of the other exterior angles.

 

Solution

 

Let the four exterior angles be x0 each.

The sum of the five exterior angles = 3600

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Hence one of the other exterior angles is 750

 

Worked Example 2

Find the value of (x+y)0 in the diagram below.

image

 

Solution

The diagram is an irregular polygon. The fact still holds.

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