Geometry in rangoli and 3D kolam designs

Rangoli can be used for teaching , there is geometry is rangoli , since rangoli designs are made using shapes like triangles , rectangles, circles and solid shapes too.

The first rangoli below is drawn using a five by five dot grid and four cuboid like designs are formed . This can be  seen in the photos below .  

The steps can be followed by following the patterns drawn in the picture.  See how easy it is to create solid shapes using rangoli ideas. 
 
Easy Geometric rangoli designs through photos | 5 by 5 dots rangoli 
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chukki rangoli 5 by 5 | white rangoli design
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By drawing dotted lines as shown in the image below we can show hollow shapes - cuboid in this case.  We should not add colours because the 3D effect will disappear
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The next rangoli is a  8 by 8 dot rangoli.  Again a number of pictures have been  shown to make the steps  in the rangoli very clear.  As I have stated , usually a kolam as we call rangoli may appear simple  when  we look at a photo but unless we try at least once we are likely to get stuck up somewhere.!  So I invariably add a number of images to show the  steps because pictorial representation is always a thousand times better than a thousand words !  Now the steps for this easy rangoli

Geometrical rangoli designs images | 8 by 8 dots rangoli 
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The arrows in yellow highlight the place where we can see two cuboids , when viewed from two directions.  The rhombus that the yellow arrows point to is the face of the cuboid.   We can  see two inclined cuboids .  Hope you can identify them.  Similarly there are four pairs in the rangoli.  We can have more such ideas.
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A basic 3D kolam with dots

The dot grid is 2,5,6,5,6,5,2.  After placing the dot grid , the first image shows the central pattern being drawn Once the central design in completed extend the the arms from each edge connecting the dots in the way as shown.
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Lines have been drawn from all the edges.  Next from the outer edge of the line draw a smaller line to the next dot below as shown in the image below ( on the left side of the kolam ).  This short line should be parallel to the next line below
Continue drawing short parallel lines on all six sides.
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From the shorter lines , draw another line ( observe the position of the hand in the image below )
This line should be parallel to the shorter line above it  so that we get a 3D effect
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The kolam is complete and solid shapes are seen in many directions.
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