8th Grade Angles in Polygons Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the 8th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Angles8th 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 quadrilateral.
Answer: 360°
- Angle sum = (n − 2) × 180°
- (4 − 2) × 180° = 360°
2.Find the size of each interior angle of a regular pentagon.
Answer: 108°
- Angle sum = (5 − 2) × 180° = 540°
- 540° ÷ 5 = 108°
3.Find the size of each exterior angle of a regular triangle.
Answer: 120°
- Exterior angles add to 360°
- 360° ÷ 3 = 120°
4.Each exterior angle of a regular polygon is 90°. How many sides does it have?
Answer: 4
- Exterior angles add to 360°
- 360 ÷ 90 = 4 sides
5.Find the sum of the interior angles of a nonagon.
Answer: 1,260°
- Angle sum = (n − 2) × 180°
- (9 − 2) × 180° = 1,260°
6.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°
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 15°. How many sides does it have?
Answer: 24
- Exterior angles add to 360°
- 360 ÷ 15 = 24 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 18-sided polygon.
Answer: 160°
- Angle sum = (18 − 2) × 180° = 2,880°
- 2,880° ÷ 18 = 160°
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