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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          CREATING SHAPES IN SCRATCH
                   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.                                                                                                73

                 •   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 command.


                                   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
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