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Chapter Profile

                         DRAWING POLYGONS IN SCRATCH


                  Polygons are 2D shapes with three or more straight lines and angles. Examples of polygons


                  are triangle, square, rectangle, quadrilateral, pentagon, octagon, etc.





                   Equilateral    Square     Pentagon     Hexagon     Heptagon     Octagon     Nonagon      Decagon
                     Triangle    (4 sides)    (5 sides)   (6 sides)    (7 sides)   (8 sides)    (9 sides)   (10 sides)
                    (3 sides)

                  To draw polygons in Scratch, you must remember a few thumb rules. They are:

                       You must know the number of sides in the shape. This is the value to be given in repeat
                      block. For example, you give repeat 3 to draw a triangle and 4 to draw a square.
                       Each time a repeat command is used, you draw a line and turn at a corner.

                       You must know the degree of the angle at the corner. It is very easy to calculate this.
                      Just divide 360 by the number of sides in the shape. For example, to draw a triangle, the

                      turn will be 360/3 (sides of the triangle) = 120.
                  Look at these polygons can be made using repeat.


                                    Polygon                                 Command


                            Triangle                   Repeat 3 Move 100 Steps Turn 120 degrees


                            Square                     Repeat 4 Move 100 Steps Turn 90 degrees

                            Pentagon                   Repeat 5 Move 100 Steps Turn 72 degrees


                            Hexagon                    Repeat 6 Move 100 Steps Turn 60 degrees


                            Heptagon                   Repeat 7 Move 100 Steps Turn 51 degrees

                            Octagon                    Repeat 8 Move 100 Steps Turn 45 degrees


                            Nonagon                    Repeat 9 Move 100 Steps Turn 40 degrees


                            Decagon                    Repeat 10 Move 100 Steps Turn 36 degrees




                                    Suppose, you have to code a dance party in Scratch where characters keep
                                    dancing in a loop until stopped? Which block will you use for this and which
                                    songs would you play in the program?




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