POLYGONS: RELATIONSHIPS WITH ANGLES & SIDES
Learn the relationships between the measures of interior & exterior angles & polygons.
Below are the angle amounts for figures that have three-sides to twelve-sides:
Formula to find sum of interior angles of any Polygon. (s-2) 180 = A
Name of Figure
Interior Angles =/Size of Interior Angle
Exterior Angles =
Triangle (3 sides) 180° / 3 = 60° 360°
Quadrilateral (4 sides) 360° / 4 = 90° 360° Pentagon (5 sides) 540° / 5 = 108° 360° Hexagon (6 sides) 720° / 6 = 120° 360° Septagon (7 sides) 900° / 7 = 128.5° 360° Octagon (8 sides) 1080° / 8 = 135° 360° Nonagon (9 sides) 1260° / 9 = 140° 360° Decagon (10 sides) 1440° / 10 = 144° 360° Hendecagon (11 sides) 1620° / 11 = 147° 360° Dodecagon (12 sides) 1800° / 12 = 150° 360°
Want to know how to find the sum of the angles of the interior angles of any polygon?
Formulas and Examples For Polygons
Learn the relationships between the measures of interior & exterior angles & polygons.
Below are the angle amounts for figures that have three-sides to twelve-sides:
Formula to find sum of interior angles of any Polygon. (s-2) 180 = A
Name of Figure | Interior Angles =/Size of Interior Angle | Exterior Angles = |
| Triangle (3 sides) | 180° / 3 = 60° | 360° |
| Quadrilateral (4 sides) | 360° / 4 = 90° | 360° |
| Pentagon (5 sides) | 540° / 5 = 108° | 360° |
| Hexagon (6 sides) | 720° / 6 = 120° | 360° |
| Septagon (7 sides) | 900° / 7 = 128.5° | 360° |
| Octagon (8 sides) | 1080° / 8 = 135° | 360° |
| Nonagon (9 sides) | 1260° / 9 = 140° | 360° |
| Decagon (10 sides) | 1440° / 10 = 144° | 360° |
| Hendecagon (11 sides) | 1620° / 11 = 147° | 360° |
| Dodecagon (12 sides) | 1800° / 12 = 150° | 360° |
Want to know how to find the sum of the angles of the interior angles of any polygon?
Formulas and Examples For Polygons