Theory:

To draw shapes(like lines, angles, polygons,...) various instruments are used.
 
One of the basic instruments is a ruler (or scale).
 
A ruler in an instruments box is graduated into centimetres along one edge. It is used to draw  lines.
 
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And the other two commonly used instruments are compass and protractor.
 
A compass has two legs, one with a point and the other with a pencil or lead. It is used to draw arcs and circles.
 
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A protractor is a tool for measuring angles, usually made of transparent plastic or glass. The majority of protractors measure angles are degrees\((°)\).
 
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