S2 - G1 :Special Quadrilaterals and Regular Polygons

Sum of Interior Angles

    

      Sum of interior angles = (n-2) x 180    (n=number of interior angles)

Sum of exterior angles of any polygon = 360^o

     A Regular Polygon has equal sides and equal angles.

Each external angle of any regular n-sided polygon = 360/n

Each Exterior angle + interior angle = 180^o

Common Polygon Name

            No. of sides                 Name of Polygon        Sum of Interior Angles

                         3                        Triangle                                 180^o

                         4                        Quadrilateral             360^o

                         5                        Pentagon                              540^o

                         6                        Hexagon                               720^o

                         7                        Heptagon                              900^o

                         8                        Octagon                                1080^o

                         9                        Nonagon                   

                        10                       Decagon

                        12                       Dodecagon