1. Count the number of sides your polygon has. The method for calculating the sum of interior angles is based on how many sides the polygon has. Remember that a polygon must have
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The total number of interior degrees in a polygon with number of sides n is 180 times (n2). For a regular octagon (meaning all sides are the same, thus all angles are the same) you
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Easy peezy my teacher taught me this: An Octagon has 8 sides and all EXterior angles add too 360 so you do 360 divided by 8 and get 45. The do 180 subtract 45 to get the interior
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