Year 8 Angles in Polygons Worksheet — Level 2 — Practice Set 4 — 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 — 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 heptagon.
Answer: 900°
- Angle sum = (n − 2) × 180°
- (7 − 2) × 180° = 900°
2.Find the size of each interior angle of a regular hexagon.
Answer: 120°
- Angle sum = (6 − 2) × 180° = 720°
- 720° ÷ 6 = 120°
3.Find the size of each exterior angle of a regular 15-sided polygon.
Answer: 24°
- Exterior angles add to 360°
- 360° ÷ 15 = 24°
4.Each exterior angle of a regular polygon is 72°. How many sides does it have?
Answer: 5
- Exterior angles add to 360°
- 360 ÷ 72 = 5 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 30-sided polygon.
Answer: 168°
- Angle sum = (30 − 2) × 180° = 5,040°
- 5,040° ÷ 30 = 168°
7.Find the size of each exterior angle of a regular 20-sided polygon.
Answer: 18°
- Exterior angles add to 360°
- 360° ÷ 20 = 18°
8.Each exterior angle of a regular polygon is 10°. How many sides does it have?
Answer: 36
- Exterior angles add to 360°
- 360 ÷ 10 = 36 sides
9.Find the sum of the interior angles of a nonagon.
Answer: 1,260°
- Angle sum = (n − 2) × 180°
- (9 − 2) × 180° = 1,260°
10.Find the size of each interior angle of a regular decagon.
Answer: 144°
- Angle sum = (10 − 2) × 180° = 1,440°
- 1,440° ÷ 10 = 144°
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