The Steiner-Lehmus theorem states that if the lengths of two of these are equal in any triangle, then the triangle is isosceles.
The Steiner-Lehmus theorem states that if the lengths of two of these are equal in any triangle, then the triangle is isosceles. They can be easily constructed by connecting a vertex of the triangle to the midpoint of the minor arc connecting the other two vertices on the circumcircle. Their namesake theorem relates the ratio in which they cut the opposing side with the ratios of two sides of the triangle. Their external versions intersect at the excenters, while their internal versions intersect at the incenter. FTP, name these lines that divide the corners of a triangle in half.
The Steiner-Lehmus theorem states that if the lengths of two of these are equal in any triangle, then the triangle is isosceles.
angle {bisector}