Chapter 2 Flashcards
Ray
The ray AB consists of the initial point a and all points on line AB that lie on the same side of a as B lies
Line segment
Segment AB consists of the endpoints a and B all-points on the line AB that lie between a and B
Opposite rays
On the line AB, if C is between a and B then CA and CB are opposite rays
Collinear
Points, segments, or rays on the same line
Angle
Consists of two different rays that have the same initial point. the rays are the sides of the angle and the initial point is the vertex of the angle
Interior of an angle
A point that lies between the sides of the angle
Exterior of an angle
A point that is not on or inside of the angle
Adjacent angle
Two angles are adjacent if they share a common vertex and side but have no common interior points
Congruent segments
Two segments that have the same length
Congruent angles
Two angles that have the same measure
Segment bisector
A segment, ray, line or ray that intersects a segment at its midpoint
Angle bisector
A ray that divides the angle into two congruent angles
Perpendicular lines
Two lines that intersect to form a right angle
A line is perpendicular to a plane if..
If it is perpendicular to each line in the plane that intersects it
Postulate 5
Through any two distinct points…
Through any two distinct points there exists exactly one line
Post 6 a line contains…
At least two points
Post 7 through any three noncollinear points…
There exists exactly one plane
Post 8 a plane contains…
At least three points
Post 9 if two distinct points lie in a plane…
Then the line containing them lies in the plane
Post 10 if two distinct planes intersect…
Them their intersection is a line
Vertical angles
Two angles whose sides form two pairs of opposite rays
Linear pair
Two adjacent angles whose noncommon sides are opposite rays
Complementary angles
Two angles are complementary if the sum of their measures is 90°
supplementary angles
Two angles are supplementary if the sum of the angles equals 180°
Linear pair postulate
If two angles form a linear pair then they are supplementary
Congruent supplements theorem
If two angles are supplementary to the same angle or congruent angles than they are congruent
Congruent complements theorem
If two angles are complementary to the same angle or congruent angles then they are congruent
Vertical angles theorem
If two angles are vertical angles then they are congruent
