Building shapes

In construction problems, we are talking about the construction of geometric figures (line segment, angle, pair of parallel straight lines, etc.) using drawing tools. Usually such tools are a ruler, compasses and a pencil.
Solving a construction problem is to find a way to construct a figure, to carry out this construction and to prove that the constructed figure is a figure with the required properties.

Using the ruler, as a tool for geometric constructions, you can:

• draw an arbitrary straight line;
• draw an arbitrary straight line passing through a given point;
• draw a straight line passing through two given points.
  
  Using a compass, you can:
  
  
• build an arbitrary circle;
• build a circle with a given center and radius;
• To postpone the given segment on a straight line from the given point.
  
  Having learned how to build "basic" geometric shapes, it will be possible to build more complex ones, after analyzing complex and reducing them to "basic" geometric shapes.