Chapter 1 Flashcards
Undefined terms
most basic figures in geometry which cannot be defined by using other figures.
Point
Names a location and has no size. It is represented by a dot.
Line
a straight path that has no thickness and extends forever.
Plane
a flat surface that has no thickness and extends forever.
Collinear
Points that lie on the same line
Coplaner
points that lie in the same plane
Segment
is the part of the line consisting of two points and all points between them.
Endpoint
is a point at one end of a segment or the starting point of a ray
Ray
part of a line that starts at an endpoint and extends forever in one direction.
Opposite rays
two rays that have a common endpoint and form a line.
Postulate
is a statement that is accepted as true without proof.
Coordinate
A number used to identify the location of a point.
Distance
between two points is the absolute value of difference of the coordinates.
Length
The absolute value of the difference between coordinates a and b
Congruent segments
segments that have the same length
Construction
way of creating a figure that is more precise (using a compass and straight edge)
Midpoint
point that bisects or divides the line into two congruent segments
Segment bisector
Segment or a line that intersects a segment at a midpoint
Angle
figure formed by two rays or sides with a common endpoint
Vertex
point formed by two rays or segments
Interior of an angle
the set of all points between the sides of the angle
Exterior of an angle
is the set of points outside the angle
Acute angle
Measures greater than 0 but less than 90
Right angle
measures 90
Obtuse angle
measures greater than 90 but less than 180
Straight angle
formed by two opposite rays and measures 180
Congruent angles
angles that have the same measure
Angle Bisector
is a ray that divides an angle into two congruent angles
Adjacent angles
two angles in the same plane with a common vertex and a common side, but no common interior points
Linear Pair
pair of adjacent angles whose non common sides are opposite rays
Complementary Angles
are angles that measure to have the sum of 90
Supplementary angles
two angles who measures have a sum of 180
Vertical Angles
two non-adjacent angles formed by two intersecting lines
