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Mathematics LibreTexts

1: Lines, Angles, and Triangles

  • Page ID
    34116
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    • 1.1: Lines
      Geometry (from Greek words meaning earth-measure) originally developed as a means of surveying land areas, In its simplest form, it is a study of figures that can be drawn on a perfectly smooth flat surface, or plane. It is this plane geometry which we will study in this bock and which serves as a foundation for trigonometry, solid and analytic geometry, and calculus.
    • 1.2: Angles
      An angle is the figure formed by two rays with a common end point, The two rays are called the sides of the angle and the common end point is called the vertex of the angle.
    • 1.3: Angle Classifications
    • 1.4: Parallel Lines
      Two lines are parallel if they do not meet, no matter how far they are extended.
    • 1.5: Triangles
      A triangle is formed when three straight line segments bound a portion of the plane, The line segments are called the sides of the triangle. A point where two sides meet is called a vertex of the triangle, and the angle formed is called an angle of the triangle, The symbol for triangle is △ .
    • 1.6: Triangle CIassifications

    Thumbnail: Angles A and B are adjacent. (Public Domain; Limaner via Wikipedia)


    This page titled 1: Lines, Angles, and Triangles is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Henry Africk (New York City College of Technology at CUNY Academic Works) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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