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

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Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Angles

Year 8 Angles in Polygons Worksheet — Level 2 — Practice Set 2 — 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 36-sided polygon.

Answer: 170°

  1. Angle sum = (36 − 2) × 180° = 6,120°
  2. 6,120° ÷ 36 = 170°
3.Find the size of each exterior angle of a regular decagon.

Answer: 36°

  1. Exterior angles add to 360°
  2. 360° ÷ 10 = 36°
4.Each exterior angle of a regular polygon is 36°. How many sides does it have?

Answer: 10

  1. Exterior angles add to 360°
  2. 360 ÷ 36 = 10 sides
5.Find the sum of the interior angles of a dodecagon.

Answer: 1,800°

  1. Angle sum = (n − 2) × 180°
  2. (12 − 2) × 180° = 1,800°
6.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°
7.Find the size of each exterior angle of a regular octagon.

Answer: 45°

  1. Exterior angles add to 360°
  2. 360° ÷ 8 = 45°
8.Each exterior angle of a regular polygon is 10°. How many sides does it have?

Answer: 36

  1. Exterior angles add to 360°
  2. 360 ÷ 10 = 36 sides
9.Find the sum of the interior angles of a heptagon.

Answer: 900°

  1. Angle sum = (n − 2) × 180°
  2. (7 − 2) × 180° = 900°
10.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°
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