Year 8 Angles in Polygons Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the Year 8 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · AnglesYear 8 Angles in Polygons Worksheet — Level 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 heptagon.
Answer: 900°
- Angle sum = (n − 2) × 180°
- (7 − 2) × 180° = 900°
2.Find the size of each interior angle of a regular 30-sided polygon.
Answer: 168°
- Angle sum = (30 − 2) × 180° = 5,040°
- 5,040° ÷ 30 = 168°
3.Find the size of each exterior angle of a regular hexagon.
Answer: 60°
- Exterior angles add to 360°
- 360° ÷ 6 = 60°
4.Each exterior angle of a regular polygon is 24°. How many sides does it have?
Answer: 15
- Exterior angles add to 360°
- 360 ÷ 24 = 15 sides
5.Find the sum of the interior angles of a hexagon.
Answer: 720°
- Angle sum = (n − 2) × 180°
- (6 − 2) × 180° = 720°
6.Find the size of each interior angle of a regular octagon.
Answer: 135°
- Angle sum = (8 − 2) × 180° = 1,080°
- 1,080° ÷ 8 = 135°
7.Find the size of each exterior angle of a regular decagon.
Answer: 36°
- Exterior angles add to 360°
- 360° ÷ 10 = 36°
8.Each exterior angle of a regular polygon is 18°. How many sides does it have?
Answer: 20
- Exterior angles add to 360°
- 360 ÷ 18 = 20 sides
9.Find the sum of the interior angles of a 11-sided polygon.
Answer: 1,620°
- Angle sum = (n − 2) × 180°
- (11 − 2) × 180° = 1,620°
10.Find the size of each interior angle of a regular triangle.
Answer: 60°
- Angle sum = (3 − 2) × 180° = 180°
- 180° ÷ 3 = 60°
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