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Gravity
Terms in this set (62)
Ordered Pair
Points on the coordinate plane (x,y)
X-Coordinate
The first number in an ordered pair that correspongs to a number on the x-axis
Y-Coordinate
The second number in an ordered pair that corresponds to a number on the y-axis
Quadrant
The four regions of the coordinate plane created by the x-axis and y-axis
Origin
The point at which the axes intersect.
Congruent
Geometric figures that have exactly the same shape and size.
Midpoint
The point halfway between the endpoints of the segment.
Segment Bisector
Any segment, line or plane that intersects a segment at it's midpoint.
Angle
Formed by two non-collinear rays that have a common endpoint
Vertex
The common endpoint of an angle
Angle Bisector
A ray that divides an angle into two congruent angles
Point
A location - it has neither shape nor size
Line
Made up of points and has no thickness or width.
Plane
A flat surface made up of points that extends infinitely in all directions
Collinear
Points that lie on the same line.
Coplanar
Points that lie in the same plane
Intersection
The set of points two or more geometric figures have in common.
Space
A Boundless 3-D set of all points
Parallel
Lines, segments, rays or planes that never intersect
Perpendicular
Lines, segments,rays or planes that form right angles.
Parallel Lines
Coplanar lines that do not intersect. Their slopes are equal.
Skew Lines
Lines that do not intersect and are not coplanar
Transversal
A line that intersects two or more lines in a plane at different points
Interior Angles
Angles that lie between two transversal that intersect the same line
Exterior Angles
An angle formed by one side of triangle and the extension of another side
Consecutive Interior Angles
Angles that are on the same-side of the transversal and are in between the parallel lines
Alternate Interior Angles
Angles that are on opposite sides of the transversal and are in between the parallel lines
Corresponding Angles
Angles that are in the same position, but a different group of angles
Alternate Exterior Angles
Angles that are on opposite sides of the transversal and are outside the parallel lines
Composition of Transformations
combination of two or more transformations
Congruent segments
line segments whose lengths are equal
Degree of Rotation
number of degrees a figure is rotated about the point (center) of rotation
Dilation
a similarity transformation in which a figure is enlarged or reduced using a scale factor and a center of dilation
Euclidean Geometry
the study of plane and solid geometry based on definitions, undefined terms (point, line, plane) and the assumptions of mathematician Euclid
Horizontal Reflectional (Line) Symmetry
reflectional symmetry about a horizontal line of reflection
Image
figure after a transformation
Line of Symmetry
- line dividing an image into two congruent parts that are mirror images of each other
Midpoint of a Line Segment
the point halfway between the endpoints of a line segment
Non-Rigid Transformation (Non-isometric)
a transformation that preserves similarity and reductions and enlargements that do not preserve similarity
Perpendicular Lines
lines in the same plane that intersect at 90 angles whose slopes are opposite reciprocals,
Point of Rotation
point around which a figure is rotated (center of rotation)
Point Symmetry
180 degree rotation around a point
Pre-Image
original figure prior to a transformation
Reflection
rigid transformation in which each point in a geometric figure is at an equal distance on the opposite side of a given line (line of symmetry)
Reflectional Symmetry
symmetry in which one half of the image is a mirror image of the other over a line of reflection
Rigid Transformation (Isometric)
a transformation that preserves the size and shape of a figure
Rotation
a rigid transformation where each point on the figure is rotated about a given point
Rotational Symmetry
symmetry that occurs if a figure can be rotated less than 360° around a central point and still look the same as the original. The number of times a figure fits into itself in one complete rotation is called the order of rotational symmetry.
Symmetric Points
two points in a plane such that the line segment joining the points is bisected by a point or center
Transformation
one to one mapping of points in a plane such that each point in the pre-image has a unique image and each point in the image has a pre-image
Translation
rigid transformation moving all points in a geometric figure the same distance and the same direction
Two-Dimensional Coordinate System
two axes at right angles to each other, forming a xy-plane, consisting of points (x, y)
Vertical Reflectional (Line) Symmetry
reflectional symmetry about a vertical line of reflection
Perpendicular Bisector
a perpendicular segment that bisects a segment
Concurrent LInes
when three or more lines intersect at a common point
Point of Concurrency
the point where concurrent lines intersect
Circumcenter
the point where perpendicular bisectors of a triangle are concurrent
Incenter
the point where angle bisectors of a triangle are concurrent
Median
a segment that connects a vertex of a triangle with the midpoint of the opposite side
Centroid
the point where the medians of a triangle are concurrent
Altitude
a segment from a vertex perpendicular to the opposite side of a triangle (can be outside the triangle)
Orthocenter
the point where the altitudes of a triangle are concurrent
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