What is the sum of the interior angles of a regular convex octagon (8-sided polygon)?
Answer and explanation
Correct answer: A. 1080 degrees
- Step 1: Use the interior angle sum formula: S = (n - 2) * 180 degrees.
- Step 2: Substitute n = 8: S = (8 - 2) 180 = 6 180.
- Step 3: Compute: 6 * 180 = 1080 degrees.
Answer
1080 degrees.
Why not the others: '1440 degrees' uses n = 10 (decagon); '720 degrees' uses n = 6 (hexagon); '900 degrees' uses n = 7 (heptagon).
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