A portion of a line which starts at a point and goes off in a particular direction.
ray
What is an exact position or location on a plane surface? (0 dimensions)
point
One part of a line that connects two points.
segment
A geometric figure formed by two lines that begin at a common point or by two planes that being at a common line.
angle
Length of a line segment.
distance
The point or set of points where one line or surface crosses another.
intersection
Two rays that have the same endpoint and extend in opposite directions.
opposite rays
It is straight and extends in two directions without end.
line
When points lie on a straight line.
collinear
When the points are positioned in a way that does not form a line.
noncollinear
When points lie in the same plane.
coplanar
A surface in which if any two points are chosen a straight line joins them on that surface.
plane
Lines/planes side by side that have the same distance between them.
parallel
Two angles that have a common vertex and a common side.
adjacent angles
Angles that do not share a vertex or side.
nonadjacent angles
Angles that add up to have the sum of ninety degrees.
complementary
Two angles that lie on the same side of a transversal and between the lines cut by the transversal.
same-side interior
When two lines are crossed by another line on opposite sides of the transversal between the lines.
alternate interior
A point on a line segment that divides it into two equal parts.
midpoint
Lines that are right angles to each other.
perpendicular
Angles opposite to each other when two lines cross.
vertical angles
A pair of adjacent,supplementary angles.
linear pairs
Angles that sum up to 180 degrees.
supplementary
A point,segment,line,or plane that divides a line segment into two equal parts.
segment bisector
A line or ray that divides an angle into two congruent angles.
angle bisector