1. 1 Angle Sum of a Polygon Stage 5 - Year 9 Press Ctrl-A ©2009 – Not to be sold/Free to use

2. 2 2 x 180 o = 360 o 180 o Quadrilateral (4) 4-2 Angle Sum of a Polygon

3. 3 3 x 180 o = 540 o 180 o Pentagon (5) 5-2 Angle Sum of a Polygon

4. 4 4 x 180 o = 720 o 180 o Hexagon (6) 180 o 6-2 Angle Sum of a Polygon

5. 5 6 x 180 o = 1080 o 180 o Octagon (8) 180 o 8-2 Angle Sum of a Polygon

6. 6 S =(n – 2)x180 o Polygon (n) n sides = Angle Sum of a Polygon

7. 7 Quadrilateral (4) S = (n -2) x 180 o = (4 -2) x 180 o = 2 x 180 o = 360 o 4 Angle Sum of a Polygon

8. 8 Pentagon (5) S = (n -2) x 180 o = (5 -2) x 180 o = 3 x 180 o = 540 o 5 Angle Sum of a Polygon

9. 9 Hexagon (6) S = (n -2) x 180 o S = (6 -2) x 180 o S = 4 x 180 o = 720 o 6 Angle Sum of a Polygon

10. 10 Hexagon (8) S = (n -2) x 180 o S = (8 -2) x 180 o S = 6 x 180 o = 1080 o 8 Angle Sum of a Polygon

11. 11 S = (n -2) x 180 o = (5 -2) x 180 o = 3 x 180 o = 540 o 5 120 o 85 o 130 o yoyoyoyo y + 130 + 120 + 85 + 130 = 540 y + 465 = 540 o - 465 -465 y = 74 o Angle Sum of a Polygon

12. 12 S = (n -2) x 180 o = (6 -2) x 180 o = 4 x 180 o = 720 o 6 120 o 130 o momomomo m + 130 + 120 + 130 + 120 + 130= 720 m + 130 + 120 + 130 + 120 + 130 = 720 m + 630 = 720 o -630 -630 m = 90 o 130 o 120 o Angle Sum of a Polygon