1. Centroid
2. Orthocenter
3. Circumcenter
4. Circumcircle
5. Incenter
6. Incircle
8. Orthocenter, Mid-segment triangle.
10. Pedal triangle
11. Center of Nine point circle
14. Equilateral triangle, given a side
16. Isosceles triangle, given base and altitude
17. Triangle Centers (H, G, C, and I)
18. Triangle Centers with Euler Line
19. Locus of vertex of a fixed angle that subtends a fixed segment.
20. Divide a segment AB into two parts that form a golden ratio.