Geometry basic constructions

Basic constructions

Video list about basic constructions (segment and angle bisector, Thales's theorem, angle addition, etc.): Basic constructions video list

Angles

Construction of a 60, 30, 120, 90, & 45 Degree Angle.

Triangles

What are the Different Types of Triangles?

• Equilateral triangle given side a.
• Isosceles triangle given base b and one side.
• Isosceles triangle given base b and altitude h.
• Scalene triangle given sides a, b and c.

Triangle Centres

• Centroid or Barycentre.
  
• Incentre.
• Circumcentre.
• Orthocentre.  
  

 

Quadrilaterals

Types of Quadrilaterals and their Properties

• Square given side a.
• Rectangle given sides a and b.
• Rectangle given diagonal d and base b.
• Right Trapezoid knowing the length of its bases and its height 
• Definitions: trapezoid and trapezium (BrE vs AmE).
• Trapezium attributes. 

Regular polygons inscribed in a circle

• General method to draw regular polygons inscribed in circles.
• Equilateral triangle inscribed in a circle.
• Square inscribed in a circle.
• Regular pentagon inscribed in a circle.
• Hexagon inscribed in a circle.
• Regular octagon inscribed in a circle. 

Regular polygons inscribed in a circle

There are some methods to construct these regular polygons and a general method that can be used for any polygon.

General method

Video list about regular polygons (triangle, square, pentagon, hexagon, etc.): Regular polygons video list