Number of sides from the sum of the interior angles
Interior angle sum = (n − 2) × 180. Work backwards to find n.
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The interior angles of a polygon add up to 1440°. How many sides does the polygon have?
Answer: 10
The interior angles of a polygon add up to 9720°. How many sides does the polygon have?
Answer: 56
The interior angles of a polygon add up to 720°. How many sides does the polygon have?
Answer: 6
Tip: Interior angle sum = (n − 2) × 180. Work backwards to find n.
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