Year 8 Angles in Polygons Worksheet — Level 1 — Practice Set 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 1 — 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 14-sided polygon.
Answer: 2,160°
- Angle sum = (n − 2) × 180°
- (14 − 2) × 180° = 2,160°
2.Find the size of each interior angle of a regular 24-sided polygon.
Answer: 165°
- Angle sum = (24 − 2) × 180° = 3,960°
- 3,960° ÷ 24 = 165°
3.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°
4.Find the size of each interior angle of a regular decagon.
Answer: 144°
- Angle sum = (10 − 2) × 180° = 1,440°
- 1,440° ÷ 10 = 144°
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 nonagon.
Answer: 140°
- Angle sum = (9 − 2) × 180° = 1,260°
- 1,260° ÷ 9 = 140°
7.Find the sum of the interior angles of an octagon.
Answer: 1,080°
- Angle sum = (n − 2) × 180°
- (8 − 2) × 180° = 1,080°
8.Find the size of each interior angle of a regular 18-sided polygon.
Answer: 160°
- Angle sum = (18 − 2) × 180° = 2,880°
- 2,880° ÷ 18 = 160°
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 hexagon.
Answer: 120°
- Angle sum = (6 − 2) × 180° = 720°
- 720° ÷ 6 = 120°
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