Recent Additions

31.

Einstein and Pythagoras theorem proof
 

30.

Hippocrates and Squaring the Circle
 

29.

Lunes of Hippocrates 4
 

28.

Lunes of Hippocrates 3
 

27.

Lunes of Hippocrates 2
 

26.

Lunes of Hippocrates 1
 

25.

Pythagoras and Circle Area
 

24.

Right Triangles, Formulas and Facts
Pythagorean theorem, Similarity, Geometric mean, hypotenuse, legs, semiperimeter, altitude, median, similar shapes areas, centers, orthocenter, incenter, centroid, circumcenter, radius, inradius, circumradius, exradius, circles, incircle, circumcircle, excircle.

23.

Mind Map of the Pythagorean Theorem
Proofs by shears, translation, similarity. Facts.
 

22.

Proposed Problem 49. Angles and right triangle.

21.

Sangaku Problem 41. "Mickey Mouse" shape: Three circles representing head and ears.

20.

Triangle and Squares 19  

19.

Proposed Problem 38.
Right Triangle, altitude, incircles, incenters, and angles.

18.

Proposed Problem 37.
Right Triangle, altitude, incircles, incenters, and orthocenter.

Problem 36.
Right Triangle, altitude, incircles and inradii.

17.

Proposed Problem 34.
Right triangle, cevian, incircles, tangents and inradius.

16.

Archimedes' Book of Lemmas
 

15.

Euler and his beautiful and extraordinary formula

14.

Problem 31. Right Triangle, Incircle, Collinears.
Problem 30. Right Triangle, Incircle, Inradius.

13.

Proposed Problem 29.
Right Triangle, altitude, incircle and inradius. Ten conclusions.

12.

Problem 29: Geometry Help.
Facts you should know.

11.

Proposed Problem 28
Right Triangle, altitude, incircles and inradius.

10.

Proposed Problem 27
Right Triangle, incircles and inradius.

9.

Proposed Problem 26
Right Triangle, altitude, incircles and inradius.

8.

Proposed Problem 25
Right Triangle, altitude, incircles and inradius.

7.

Proposed Problem 24
Right Triangle, altitude, incircles and inradii.

6.

Proposed Problem 23
Right Triangle, altitude, incircles and inradii.

5.

Proposed Problem 22
Right Triangle, altitudes, incircles and inradii.

4.

Proposed problem 20
Right Triangle, incircles and inradii.

3.

Proposed problem 19
Right Triangle and Excenter

2.

Poncelet Theorem

1.

Sangaku Problem 3

Geometry: Right Triangles - Topics

• Pythagorean theorem, Geometric mean, Product of the legs, altitude, Projection

• Special Right Triangles

• Centers, Inradius, Circumradius, Incenter, Circumcenter, Orthocenter, Centroid, Poncelet, Sagitta

• Inradius, Exradii, Semiperimeter, Area

• Orthogonal Projections

• Altitude, Inradii, Incenter, Areas

• Pythagorean Theorem: Diagonal of a Box

• Distance in Cartesian Coordinate

• De Gua's Theorem

• Einstein and Pythagoras theorem proof

• Squaring the circle? Lunes 1, 2, 3, 4, 5

• Mind Map of the Pythagorean Theorem

• Problems: 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 34, 36, 37, 38, 41, 49