Unit 1- The Language Of Geometry Flashcards
A line
- Goes on forever in both directions
- Named with only 2 points on a line or a lower case letter
A point
- Lies on a coordinate
- Named with a capital letter
A plane
-named with 3 points that are not all on the same line or 1 single capital letter with a plane by it
Line postulate
Through any 2 points is exactly 1 line
Plane postulate
Through any 3 points that are not on the same line, there is exactly 1 plane
Segment
A line with a definite starting point and stopping point
Ray
A line that has one definite point but the other goes on forever
Collinear points
Points that lie on the same line
Opposite rays
2 rays that have the same starting point but go on in opposite directions
Congruent segments
Line segments that are the same length
Midpoint
The middle of a line segment
Segment bisector
When 2 lines, line segments or Rays intersect directly in the center of the other
Coplanar points
Points that aren’t all on the same line
Intersection
2 or more geometric figures intersect if they have 1 or more points in common
Distance
The distance between points A&B is the absolute value of the difference between their coordinates
(In geometry),A rule that is accepted without proof is called a…
Postulate or axiom
If B is between A and C, then…
AB+BC=AC (lengths)
If AB+BC=AC, then…
B is between A&C
Lengths are _____
Segments are ____
Equal
Congruent
Angle
Two Rays that are connected at the same point (vertex)
Acute angle
Angle measuring 0-90 degrees
Right angle
Angle that is exactly 90 degrees
Perpendicular lines
Lines that intersect to make all right angles
Obtuse angles
Angles that measure 90-180 degrees
