Geometry: Marion Walter's Theorem and Related Topics

Marion Walter's Theorem, Problem 122.
Area of triangle and Hexagon, Trisection of Sides.

Marion Walter's Theorem: Triangle and Hexagon areas:
Using TracenPoche Dynamic Geometry Software.

Problem 61: Triangle, Trisection of Sides

Puzzle: Marion Walter's theorem. Puzzle cut: 12 Piece ZigZag
Based on Marion Walter's theorem

Problem 125. Area of Triangle, Star, Trisection of Sides.

Problem 124. Area of triangle, Similarity, Trisection of Sides.

Problem 123. Area of triangle, Similarity, Trisection of Sides.

Problem 121. Similarity and Area of triangle, Trisection of Sides.

Ceva's Theorem. Concurrency. Interactive proof with animation. Key concept: Menelaus Theorem. 

Menelaus' Theorem. Interactive proof with animation and key concepts.
Transversal line.

Routh's Theorem - Index
Triangle, Cevians, Area, Ratio.
Transversal line. 

Routh's Theorem 1.
Triangle, Cevians, Ratio of Areas.

Routh's Theorem 2.
Triangle, Cevians, Ratio of Areas.

Routh's Theorem 3.
Triangle, Cevians, Ratio of Areas.

Routh's Theorem 4.
Triangle, Cevians, Ratio of Areas.

Problem 434.
Quadrilateral, Transversal, Ratio, Measurement, Similarity.

Problem 398.
Parallelogram, Area, Similarity, Congruence.

Problem 286: Square, Midpoints, Octagon.

Problem 239. Square, Midpoints, Lines, Congruence, Pythagoras.

Problem 178. Quadrilateral, Trisection of sides, Area.  

Problem 177. Parallelogram with Midpoints, Triangles, Areas.  

Problem 176. Quadrilateral with Midpoints, Triangles, Areas.  

Problem 175. Quadrilateral with Midpoints, Areas.  

Problem 174. Quadrilateral with Midpoints, Triangles, Areas.  

Problem 173. Quadrilateral with Midpoints, Triangles, Areas.  

Problem 172. Trapezoid, Midpoints, Quadrilaterals, Areas.  

Problem 171. Trapezoid, Midpoints, Triangles, Areas.  

Problem 169. Parallelogram, Interior and Exterior Points, Diagonals, Pentagon, Triangles, Areas.  

Problem 168. Parallelogram, Diagonal, Triangles, Pentagon, Areas.  

Problem 167. Parallelogram, Diagonal, Triangles, Areas.  

Problem 166. Parallelogram, Diagonal, Triangles, Areas.  

Problem 165. Parallelogram, Diagonal, Triangles, Areas.  

Problem 164. Parallelogram, Trapezoid, Diagonal, Triangles, Areas.  

Problem 163. Trapezoid, Diagonals, Triangles, Areas.  

Problem 162. Parallelogram, Triangles, Areas.  

Problem 161. Parallelogram, Midpoints, Octagon, Areas.  

Problem 151. Quadrilateral, Area, Trisection of Sides.

Problem 150. Quadrilateral, Area, Trisection of Sides.

Problem 149. Quadrilateral, Area, Midpoints.

Problem 148. Quadrilateral, Area, Midpoints.

Problem 147. Quadrilateral, Area, Midpoints, Triangle.

Problem 110. Area of Contact Triangle.