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What is the area of a regular polygon with 16 sides and side length 4 inches

2 Answers

6 votes
you take 16 and multiply it by 4, giving you the answer that the area is 64
User Vasyl Demin
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3 votes

For a better understanding of the solution please find the diagram in the attached file.

The diagram is that of a triangular part of the regular polygon. The triangle
\Delta OAB is an isosceles triangle because the sides OA and OB are equal. Now, The angle
\angle OAB=(360^(\circ))/(16)=22.5^(\circ). This is because the angle around the central angle of a polygon is 360 degrees in total.

Now, because
\Delta OAB is an isosceles triangle, angle OAP will be half of angle OAB. Thus,
\angle OAP=11.25^(\circ).

AP will be half of AB. Therefore, AP=2.

Now, the apothem, OP can thus be found as:


(AP)/(OP)=tan(11.25^(\circ))


\therefore OP=(AP)/(tan(11.25^(\circ)))=(2)/(tan(11.25^(\circ)))\approx10.1

Thus the area of one triangle is
(1)/(2)* 4* 10.1=20.2

Therefore, the area of all the 16 triangles that make up the regular polygon is:
16* 20.2=323.2

Thus the area of the polygon is 323.2 squared inches.

What is the area of a regular polygon with 16 sides and side length 4 inches-example-1
User MevatlaveKraspek
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5.2k points