by Soo Jin Lee
1. Centroid
2. Orthocenter
3. Circumcenter
4. Circumcircle
5. Incenter
6. Incircle
the triangle formed by joining the midpoints of the sides of a triangle
8. Orthocenter, Mid-segment triangle;
a Mid-Segment Triangle is a triangle created from a larger triangle. Once the orthocenter on the larger triangle is constructed, the mid-segment triangle uses the midpoint of each vertex to the orthocenter as the vertices.
9. Orthic triangle;
an Orthic Triangle is similar to a medial triangle, but uses the intersection points of the altitudes of the larger triangle as its vertices.
10. Pedal triangle;
the pedal triangle of P is the triangle whose polygon vertices are the feet of the perpendiculars from P to the side lines.
11. Center of Nine point circle;
the nine-point circle, also called Euler's circle or the Feuerbach circle, is the circle that passes through the feet of the perpendicular , , and dropped from the vertices of any triangle on the sides opposite them.
the nine-point circle, also called Euler's circle or the Feuerbach circle, is the circle that passes through the feet of the perpendicular , , and dropped from the vertices of any triangle on the sides opposite them.
If you click thrisectiong line segmetn, you can see the segment AB is trisected by two points D, E.
14. Equilateral triangle, given a side
16. Isosceles triangle, given base and altitude
17. Triangle Centers
18. Triangle Centers with Euler Line;
The line on which the orthocenter, triangle centroid, circumcenter, nine-point center, and number of other important triangle centers lie.
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.
