Pre-AP Geometry Terms Flashcards

Basic Geometric Terms

• Point: Represents a precise location in space without any dimension.
• Line: A straight collection of infinitely many points extending in two directions.
• Plane: A flat two-dimensional surface that extends infinitely in width and length, but has no thickness.

Relationships and Configurations

• Collinear Points: A set of points that all lie on the same straight line.
• Coplanar Points: Points that all reside on the same plane.

Line Concepts

• Line Segment: A part of a line defined by two endpoints and all points in between.
• Congruent Segments: Line segments that share identical lengths.
• Midpoint: A point on a segment that divides it into two equal lengths.

Rays and Angles

• Ray: A part of a line that starts at one point and extends infinitely in one direction.
• Angle: Formed by two noncollinear rays sharing a common endpoint called the vertex.
• Angle Bisector: A ray that divides an angle into two equal angles.

Types of Lines and Their Intersections

• Parallel Lines: Lines in the same plane that never intersect.
• Perpendicular Lines: Lines that intersect at right angles (90 degrees).
• Perpendicular Bisector: A line that bisects another line segment at a right angle.

Angle Classifications

• Acute Angle: Measures less than 90 degrees.
• Right Angle: Measures exactly 90 degrees.
• Obtuse Angle: Measures more than 90 degrees.
• Straight Angle: Measures exactly 180 degrees, forming a straight line.

Angle Relationships

• Linear Pair of Angles: Two adjacent angles that sum to 180 degrees (supplementary).
• Vertical Angles: Opposite angles formed by the intersection of two lines, usually appearing as an "X". They are congruent.
• Congruent Angles: Angles that have identical measures.
• Complementary Angles: Two angles whose measures sum to 90 degrees.
• Supplementary Angles: Two angles whose measures sum to 180 degrees.

Shapes and Their Properties

• Perimeter: The total length of the boundary of a polygon.
• Regular Polygon: A polygon that is both equilateral (all sides equal) and equiangular (all angles equal).
• Equilateral Polygon: A polygon in which all sides are congruent.
• Equiangular Polygon: A polygon with all angles equal.

Special Segments in Polygons

• Diagonal of Polygon: A segment connecting two nonadjacent vertices.
• Altitude: A perpendicular segment from a vertex to the opposite side or its extension.
• Median: A segment drawn from a vertex to the midpoint of the opposite side.

Triangle Classifications

• Acute Triangle: Contains three acute angles.
• Right Triangle: Contains exactly one right angle.
• Obtuse Triangle: Contains exactly one obtuse angle.
• Equiangular Triangle: All angles equal, each measuring 60 degrees.
• Scalene Triangle: All sides have different lengths.
• Isosceles Triangle: At least two sides are of equal length.
• Equilateral Triangle: All three sides and angles are equal.

Quadrilaterals

• Trapezoid: A quadrilateral with one pair of parallel sides.
• Kite: A quadrilateral with two pairs of adjacent congruent sides.
• Parallelogram: Opposite sides are parallel and equal.
• Rhombus: A parallelogram with all sides equal.
• Rectangle: A parallelogram with all angles equal (90 degrees).
• Square: A rectangle that is also a rhombus (equal sides).

Circle Geometry

• Circle: A set of all points equidistant from a central point (the radius).
• Radius: Distance from the center of the circle to any point on the circle.
• Diameter: A chord that passes through the center of the circle.
• Congruent Circles: Circles with the same radius.
• Concentric Circles: Circles with the same center but different radii.

Arc Measurements

• Minor Arc: An arc measuring less than 180 degrees, labeled with two points.
• Major Arc: An arc measuring more than 180 degrees, labeled with three points.
• Semicircle: An arc measuring exactly 180 degrees.
• Chord: A line segment connecting any two points on a circle.
• Tangent: A line that touches the circle at exactly one point.
• Secant: A line that intersects the circle at two points.

Test your understanding of essential geometry terms with these flashcards. This quiz covers fundamental concepts such as points, lines, planes, and more. Perfect for Pre-AP Geometry students looking to solidify their knowledge.