The sum of all the interior angles of an ‘n’ sided polygon = (n - 2) × 180∘
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Here, number of sides = 5
Therefore, sum of the interior angles = (5-2)× 180∘
= 3 × 180∘
= 540∘
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x is the measure of one of the interior angles of the pentagon.
Since it is a pentagon with each side and interior angle equal, so we conclude that each angle = x
= 540/5
= 108∘
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