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    DRAWING SHAPES USING CONTROL BLOCKS

                     The shapes can also be drawn using different Control blocks.

                     REPEAT BLOCK

                     If you want to repeat a block of code a fixed number of times, the Repeat block is used.
                     With the Repeat block, you can draw Polygons. Examples of polygons are triangle, square,

                     pentagon, hexagon, heptagon, octagon, nonagon, decagon, etc.
                     Look at these polygons that can be made using the repeat block.

                                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]

                     To draw polygons in Scratch, you must remember three points:

                     1.   You must know the number of sides in the shape. This is the value to be given in repeat
                        block.

                     2.  Each time a repeat command is used, you draw a line and turn at a corner.

                     3.  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.

                     Drawing a Square With and Without Using Repeat Block

                     Create the given Script and observe the sprite moving and turning only four times to draw

                     a square using repeat block. Click four times on the       when     clicked   block to draw a square

                     without using repeat block.

                                                                                             Drawing Shapes in Scratch  105

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