It has no dimensions and is represented by a dot
Point
It has 1 dimension and is represents by a line with two arrowheads
line
It has 2 dimensions and is represented by a figure that looks like a floor or wall
plane
A part of a line that has two endpoints
segment
A part of a line that has one end point and extends forever in one direction
ray
The points in which two or more geometric figures cross each other
intersection
When two segments have the same length or two angles have the same measure they are said to be _____.
congruent
The point directly in the middle of a segment
midpoint
A figure that cuts a segment or angle in half
bisector
An angle whose measure is less than 90 degrees
acute
An angle whose measure is exactly 90 degrees
right
An angle whose measure is greater than 90 degrees but less than 180 degrees
obtuse
An angle whose measure is exactly 180 degrees
straight
The point where the two sides of an angle intersect
Vertex
When the measure of two angles add up to 90 degrees they are said to be _____.
complementary
When the measure of two angles add up to 180 degrees they are said to be _____.
supplementary
Two angles that are next to each other and form a straight line are called a _____ pair.
linear
Two angles that are across from each other and form an "X" are called _____ angles.
vertical
When two lines never intersect, they are said to be _____.
parallel
When two lines intersect at a 90 degree angle they are said to be _____.
perpendicular
A triangle where no sides are congruent
scalene
A triangle where two sides are congruent
isosceles
A triangle where all three sides are congruent
Equilateral
A segment that connects the midpoints of two sides of a triangle
midsegment
a line that goes through a vertex of a triangle and intersects the opposite side at its midpoint
median
A line that goes through a vertex of a triangle and intersects the opposite side at a right angle.
altitude
The point where all three perpendicular bisectors of a triangle intersect
circumcenter
The point where all three angle bisectors of a triangle intersect
Incenter
The point where all three medians of a triangle intersect
centroid
The point where all three altitudes of a triangle intersect
orthocenter