Idiot\'s Guides Basic Math and Pre-Algebra

Chapter 13: Triangles 167

You can bisect any one of the angles in a triangle. The line segment from the vertex to the
opposite side that cuts the angle into two congruent angles will not necessarily cut the opposite
side in half. It’s an angle bisector, not a segment bisector.

DEFINITION

An angle bisector in a triangle is a line segment from a vertex to the opposite side

that divides the angle at that vertex into two congruent angles.

The segment drawn from angle B to side AC bisects angle B by cutting it into two angles of equal size.

The line segment from a vertex to the midpoint of the opposite side is called a median.

DEFINITION

A median of a triangle is a line segment that connects a vertex to the midpoint of the

opposite side.

The segment drawn from angle B to the midpoint of side AC divides AC into two equal segments but

does not bisect angle B.

A C

B

A C

B