Geometry: Lines and Angles Flashcards

Points, Lines, and Angles

• Point: Defines an exact location in space, often represented by a dot.
• Line: A straight path extending infinitely in two opposite directions, composed of infinite points.
• Line Segment: A portion of a line that has two distinct endpoints, unlike a full line.
• Ray: A part of a line that starts at an endpoint and extends infinitely in one direction.

Angles

• Angle: Created when two rays share a common endpoint, known as the vertex.
• Vertex: The intersection point of two rays or the meeting point of polygon sides and edges in a solid figure.

Types of Angles

• Right Angle: Measures exactly 90 degrees, forming a square corner.
• Acute Angle: Measures less than 90 degrees, appearing sharp or narrow.
• Obtuse Angle: Measures more than 90 degrees, appearing wider than a right angle.

Line Relationships

• Parallel Lines: Never intersect in a plane, maintaining a constant distance apart.
• Intersecting Lines: Two or more lines that cross at a single point.
• Perpendicular Lines: Intersect at right angles, creating four 90-degree angles at the point of intersection.