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## Comment on

Octagon Angle## For this one, I found the

## Great reasoning, Marlon!

Great reasoning, Marlon!

Yes, that technique will always work. Here's why.

We know that the sum of the angles in an n-sided polygon = 180(n - 2)

So, if we have a REGULAR n-sided polygon, the measurement of each angle = 180(n - 2)/n

Now take: 180(n - 2)/n

Expand to get: (180n - 360)/n

Rewrite as: 180n/n - 360/n

Simplify: 180 - 360/n

In your solution, you take 360/n and subtract this from 180 degrees.

In other words, the measurement of each angle = 180 - 360/n, which is the same as the expression we derived from the formula.