What is the sum of the interior angles of a convex octagon (8-sided polygon)?
Answer and explanation
Correct answer: C. 1,080°
- Step 1: Sum of interior angles formula: S = (n - 2) × 180°. Step 2. For n = 8: S = (8 - 2) × 180° = 6 × 180° = 1,080°. Answer: 1,080°. Why not the others: 1,440° is for a decagon (n = 10); 900° is for a heptagon (n = 7); 1,260° is for a nonagon (n = 9).
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