# geometry

posted by
**denise** on
.

The medial triangle of a triangle ABC is the triangle whose vertices are located at the midpoints of the sides AB, AC, and BC of triangle ABC. From an arbitrary point O that is not a vertex of triangle ABC, you may take it as a given fact that the location of the centroid of triangle ABC is the vector (vector OA + vector OB + vector OC)/3.

Task:

A. Use vector techniques to prove that a triangle and its medial triangle have the same centroid, stating each step of the proof.

1. Provide written justification for each step of your proof.