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Difficulty: 1/102022 NMTC 2022 (QII-64)

Polygon with 9 sides is called

Guide / Hint

Hint 1: Recall the standard prefix for 'nine' in polygon nomenclature.

Hint 2: Look at the Greek and Latin prefixes for numbers. The prefix 'nona-' or 'ennea-' is commonly used for the number nine in geometry.

Hint 3: Write 'nonagon' as the answer.

Solution

Step 1 (Polygon Naming Rules): Polygons are named according to their number of sides/vertices:

  • 3 sides: triangle

  • 4 sides: quadrilateral

  • 5 sides: pentagon

  • 6 sides: hexagon

  • 7 sides: heptagon

  • 8 sides: octagon

  • 9 sides: nonagon

Step 2 (Conclusion): A polygon with 9 sides is called a nonagon.

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