Term

Definition
A segment (or line, ray, or plane) that is perpendicular to a segment at its midpoint. 


Term

Definition
Having the same distance from two points or lines. 


Term

Definition
When three or more lines (or rays or segments) intersect at the same point. 


Term

Definition
The point of intersection of three or more concurrent lines. 


Term
Circumcenter of a triangle 

Definition
The point of concurrency of the three perpendicular bisectors of a triangle. 


Term
Angle Bisector of a Triangle 

Definition
A bisector of an angle of the triangle. 


Term

Definition
The point of concurency of the three angle bisectors of a triangle. 


Term

Definition
A segment in a triangle whose endpoints are a vertex of the triangle and the midpoint of the opposite side. 


Term

Definition
The point of concurrency of the three medians of the triangle. 


Term

Definition
The perpendicular segment from a vertex to the opposite side or the line that contains the opposite side. 


Term
Orthocenter of a Triangle 

Definition
The point of concurrency of the three altitudes of a triangle. 


Term

Definition
A segment that connects the midpoints of two sides of a triangle. 


Term

Definition
A proof in which you prove that a statement is true by first assuming that its opposite is true. 

