7th Grade Angles in Polygons Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the 7th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Angles7th Grade 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 20-sided polygon.
Answer: 3,240°
- Angle sum = (n − 2) × 180°
- (20 − 2) × 180° = 3,240°
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 15-sided polygon.
Answer: 24°
- Exterior angles add to 360°
- 360° ÷ 15 = 24°
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 decagon.
Answer: 1,440°
- Angle sum = (n − 2) × 180°
- (10 − 2) × 180° = 1,440°
6.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°
7.Find the size of each exterior angle of a regular pentagon.
Answer: 72°
- Exterior angles add to 360°
- 360° ÷ 5 = 72°
8.Each exterior angle of a regular polygon is 45°. How many sides does it have?
Answer: 8
- Exterior angles add to 360°
- 360 ÷ 45 = 8 sides
9.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°
10.Find the size of each interior angle of a regular nonagon.
Answer: 140°
- Angle sum = (9 − 2) × 180° = 1,260°
- 1,260° ÷ 9 = 140°
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