Four Triangles Equal in Perimeter

Proposed Problem 1

What is the relationship between the perimeters of the four triangles obtained by joining the midpoints of the sides of a triangle?














Conjecture


The preimeter of the four triangles obtained by joining the midpoints of the sides of a triangle is equal.
Please enable Java for an interactive construction (with Cinderella).
Drag free points A, B, or C to realize that the preimeter of the four triangles obtained by joining the midpoints of the sides of a triangle is equal.