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Year 8 Angles in Polygons Worksheet — Level 2 — Practice Set 4 — Answers

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Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Angles

Year 8 Angles in Polygons Worksheet — Level 2 — Practice Set 4 — Answers

Interior angle sum = (n − 2) × 180°. The exterior angles of any convex polygon add to 360°.

1.Find the sum of the interior angles of a 11-sided polygon.

Answer: 1,620°

  1. Angle sum = (n − 2) × 180°
  2. (11 − 2) × 180° = 1,620°
2.Find the size of each interior angle of a regular 24-sided polygon.

Answer: 165°

  1. Angle sum = (24 − 2) × 180° = 3,960°
  2. 3,960° ÷ 24 = 165°
3.Find the size of each exterior angle of a regular nonagon.

Answer: 40°

  1. Exterior angles add to 360°
  2. 360° ÷ 9 = 40°
4.Each exterior angle of a regular polygon is 24°. How many sides does it have?

Answer: 15

  1. Exterior angles add to 360°
  2. 360 ÷ 24 = 15 sides
5.Find the sum of the interior angles of a hexagon.

Answer: 720°

  1. Angle sum = (n − 2) × 180°
  2. (6 − 2) × 180° = 720°
6.Find the size of each interior angle of a regular 15-sided polygon.

Answer: 156°

  1. Angle sum = (15 − 2) × 180° = 2,340°
  2. 2,340° ÷ 15 = 156°
7.Find the size of each exterior angle of a regular 18-sided polygon.

Answer: 20°

  1. Exterior angles add to 360°
  2. 360° ÷ 18 = 20°
8.Each exterior angle of a regular polygon is 12°. How many sides does it have?

Answer: 30

  1. Exterior angles add to 360°
  2. 360 ÷ 12 = 30 sides
9.Find the sum of the interior angles of a quadrilateral.

Answer: 360°

  1. Angle sum = (n − 2) × 180°
  2. (4 − 2) × 180° = 360°
10.Find the size of each interior angle of a regular 30-sided polygon.

Answer: 168°

  1. Angle sum = (30 − 2) × 180° = 5,040°
  2. 5,040° ÷ 30 = 168°
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