Lessons 1-1, 1-2, 1-3 Vocab Flashcards
Undefined Term
A figure that cannot be defined by other figures
Point
A point names a location.
Line
A straight path that extends forever
Plane
A flat surface that extends forever
Segment
The part of a line consisting of two points and all points between them.
Endpoint
A point at one end of a segment / starting point of a ray
Ray
A part of a line that starts at an endpoint
Opposite Rays
Two rays that have a common endpoint and form a line
Collinear
Points that lie on the same line
Coplanar
Points that lie on the same plane.
Coordinate
A point that corresponds to a number on a ruler
Length
Distance between 2 points; the absolute value of them.
Congruent Segments
Segments with the same length
Construction
A figure with precise measurements
Midpoint
The point that bisects (divides) the segment
Segment Bisector
A ray, segment, or line that intersects a segment.
Angle
Figure formed by 2 rays
Vertex
A common endpoint of an angle
Interior Angle
All points between the sides of an angle
Exterior Angle
All points outside the angle
Measure
Usually given in degrees
Degree
1/360 of a circle
Acute Angle
0-90 degrees
Right Angle
90 degrees
Obtuse Angle
90-180 degrees
Straight Angle
180 degrees
Congruent Angles
Angles with the same measure
Angle Bisector
Ray that divides an angle into two congruent angles