2017-18. Polygonal shapes

Geometry constructions using a compass and straightedge.

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.

Quadrilaterals

• Square given side a.
• Rectangle given sides a and b.
• Rectangle given diagonal d and base b.
• Definitions: trapezoid and trapezium (BrE vs AmE).
• Trapezium attributes. 

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. 

Triangle, hexagon, square and octagon. DPG E1E

Square, trapezium and rectangles AVS E1E

Hexagon and heptagon. CGI E1E

Pentagon AAM E1D

Nonagon. LAG E1E