Section 5-1 Perpendiculars and Bisectors
Perpendicular bisector A segment, ray, line, or plane that is perpendicular to a segment at its midpoint
Equidistant from two points A point that is the same distance from each point.
Perpendicular bisector theorem If a point is on the perpendicular bisector of a segment, then it is equidistant from the endpoints of the segment.
A B C P
Converse of the perpendicular bisector theorem If a point is equidistant from the endpoints of a segment, then it is on the perpendicular bisector of the segment.
A B C P
Distance from a point to a line The length of the perpendicular segment from the point to the line. –D–Distance must be perpendicular! –L–Look for right angle!
P m
Equidistant from two lines When a point is the same distance from one line as it is from another line
Angle bisector theorem If a point is on the bisector of an angle, then it is equidistant from the two sides of the angle.
A B C If then D
Converse of the angle bisector theorem If a point is in the interior of an angle and is equidistant from the sides of the angle, then it lies on the bisector of the angle.
A B C If then D