Lecture
This lecture covers the concepts of mediatrix and bisector in right-angled triangles. Starting with the definition and properties of mediatrix, it explains how it is perpendicular to the line segment and equidistant from its endpoints. The lecture then delves into the bisector, showing how it divides the angle into two equal parts. Through step-by-step proofs and constructions, the instructor demonstrates the properties and applications of these geometric tools, providing a comprehensive understanding of their role in triangle geometry.