Year 7 Angles in Polygons Worksheet — Level 2 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 7 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · AnglesYear 7 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 quadrilateral.
Answer: 360°
- Angle sum = (n − 2) × 180°
- (4 − 2) × 180° = 360°
2.Find the size of each interior angle of a regular 20-sided polygon.
Answer: 162°
- Angle sum = (20 − 2) × 180° = 3,240°
- 3,240° ÷ 20 = 162°
3.Find the size of each exterior angle of a regular nonagon.
Answer: 40°
- Exterior angles add to 360°
- 360° ÷ 9 = 40°
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 pentagon.
Answer: 540°
- Angle sum = (n − 2) × 180°
- (5 − 2) × 180° = 540°
6.Find the size of each interior angle of a regular triangle.
Answer: 60°
- Angle sum = (3 − 2) × 180° = 180°
- 180° ÷ 3 = 60°
7.Find the size of each exterior angle of a regular quadrilateral.
Answer: 90°
- Exterior angles add to 360°
- 360° ÷ 4 = 90°
8.Each exterior angle of a regular polygon is 12°. How many sides does it have?
Answer: 30
- Exterior angles add to 360°
- 360 ÷ 12 = 30 sides
9.Find the sum of the interior angles of a hexagon.
Answer: 720°
- Angle sum = (n − 2) × 180°
- (6 − 2) × 180° = 720°
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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