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What is the measure of an interior angle of a 21-gon?162.86°90°360°3420°

User Ninaj
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1 Answer

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Question:

What is the measure of an interior angle of a 21-gon?

Concept:

Define a 21-gon

A 21-gon is a 21 sided polygon also know as An icosikaihenagon

In the case of this polygon, the value of n is


n=21

We will then calculate the sum of interior angles of a 21-gon and then divide the sum by the number of sides n...

Therefore,

The formula we will use to calculate the measure of an interior angle of a 21-gon is given below as


\begin{gathered} \text{meausre of an interior angle=}\frac{\text{sum of interior angles}}{\text{total number of sides}} \\ \end{gathered}

The formula for the sum of interior angles is given below as


\text{sum of interior angle=(n}-2)*180

Hence,

We will have


\begin{gathered} \text{meausre of an interior angle=}\frac{\text{sum of interior angles}}{\text{total number of sides}} \\ \text{meausre of an interior angle}=((n-2)*180^0)/(n) \end{gathered}

Step 2:

Substitute the value of n=21 in the formula above, we will have


\begin{gathered} \text{measure of an interior angle}=((n-2)*180^0)/(n) \\ \text{measure of an interior angle}=((21-2)*180^0)/(21) \\ \text{measureof an interior angle}=(19*180^0)/(21) \\ \text{measure of an interior angle}=(19*180^0)/(21) \\ \text{measure of an interior angle}=(3420^0)/(21) \\ \text{measure of an interior angle}=162.86^0 \end{gathered}

Hence,

The final answer = 162.86°

User Joff
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