Centroid

Orthocenter

Circumcenter

Circumcircle

Incenter

Incircle

Medial Triangle

Orthocenter, Mid-segment triangle

Orthic triangle

Pedal triangle

Nine Point Center

Nine point Circle

Trisecting a line segment

Equilateral triangle, given a side

Square, given a side

Isosceles triangle, given base and altitude

Triangle Centers (H, G, C, and I

Triangle Centers with Euler Line

Divide a segment AB into two parts that form a golden ratio

Pentagon, given a side

Hexagon, given a side

Octagon, given a side