THE BASIC GEOMETRY

• Point: A location in space with no size or dimension, represented by a dot and usually named with a capital letter (e.g., A, B).
• Line: A straight one-dimensional figure extending infinitely in both directions, with no thickness. It is usually represented with a lowercase letter or two points on the line (e.g., line lll or line ABABAB).
• Ray: A part of a line that starts at one point and extends infinitely in one direction (e.g., ray ABABAB).
• Angle: Formed by two rays (sides of the angle) with a common endpoint (vertex). Measured in degrees.
• Acute Angle: An angle less than 90 degrees.
• Right Angle: An angle of exactly 90 degrees
• Obtuse Angle: An angle greater than 90 degrees but less than 180 degrees.
• Straight Angle: An angle of exactly 180 degrees.
• Triangle: A three-sided polygon. Types include equilateral, isosceles, and scalene.
• Quadrilateral: A four-sided polygon. Types include square, rectangle, parallelogram, rhombus, and trapezoid.
• Polygon: A closed figure with three or more straight sides
• Circle: A set of all points in a plane that are equidistant from a fixed point called the center.
• Parallel Lines: Lines in a plane that never intersect and are always the same distance apart.
• Line Segment: A part of a line that has two endpoints (e.g., segment ABABAB).


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• Perpendicular Lines: Lines that intersect at a right angle (90 degrees).


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• Similar: Figures that have the same shape but may have different sizes. Corresponding angles are equal, and corresponding sides are proportional.


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• Perimeter: The total distance around the boundary of a polygon.


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• Area: The amount of space inside a two-dimensional figure.


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• Volume: The amount of space inside a three-dimensional object.


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• Coordinate Plane: A plane divided by a horizontal line (x-axis) and a vertical line (y-axis) used to locate points.


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• Origin: The point of intersection of the x-axis and y-axis in the coordinate plane, denoted as (0,0).


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  A) origin

  
• Slope: A measure of the steepness of a line, calculated as the rise over the run (change in y over change in x).


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• Congruent: Figures or angles that have the same size and shape.

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  A) Congruent