Year 7 Angles in Polygons Worksheet — Level 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 — 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 pentagon.
Answer: 540°
- Angle sum = (n − 2) × 180°
- (5 − 2) × 180° = 540°
2.Find the size of each interior angle of a regular 36-sided polygon.
Answer: 170°
- Angle sum = (36 − 2) × 180° = 6,120°
- 6,120° ÷ 36 = 170°
3.Find the size of each exterior angle of a regular 18-sided polygon.
Answer: 20°
- Exterior angles add to 360°
- 360° ÷ 18 = 20°
4.Each exterior angle of a regular polygon is 30°. How many sides does it have?
Answer: 12
- Exterior angles add to 360°
- 360 ÷ 30 = 12 sides
5.Find the sum of the interior angles of a 15-sided polygon.
Answer: 2,340°
- Angle sum = (n − 2) × 180°
- (15 − 2) × 180° = 2,340°
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 36-sided polygon.
Answer: 10°
- Exterior angles add to 360°
- 360° ÷ 36 = 10°
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 14-sided polygon.
Answer: 2,160°
- Angle sum = (n − 2) × 180°
- (14 − 2) × 180° = 2,160°
10.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°
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