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0: Introductory Geometry

  • Page ID
    247235
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    • 0.0: Prelude to Introductory Geometry
      This page emphasizes the triangle's essential role in plane geometry, serving as a foundational shape for understanding other geometric figures. It explains that any polygon with more than three sides can be divided into triangles, illustrating how the properties of triangles can be applied to various shapes and underlining their significance in geometry.
    • 0.1: Triangles
      This page explains the definition and properties of triangles, which are formed by three sides and three vertices where the sum of the angles always equals 180°. Triangles can be classified by side lengths into equilateral, isosceles, and scalene, and by angles into acute, obtuse, equiangular, and right. Each classification reveals specific properties and relationships related to triangles.
    • 0.2: Pythagorean Theorem
      In a right triangle, the square of the hypotenuse is equal to the sum of the squares of the legs.
    • 0.3: Special Right Triangles
      There are two kinds of right triangle which deserve special attention: the 30°−60°−90° right triangle and the 45°−45°−90° right triangle.
    • 0.E: Introductory Geometry (Exercises)
      This page explores fundamental principles of triangles, focusing on techniques to find missing angles and side lengths. It introduces the Pythagorean Theorem for solving unknown values in right triangles, accompanied by examples for practice. Additionally, it covers special right triangles and the relationships between their sides. Overall, this page reinforces the understanding of triangle properties and the application of mathematical principles for solving related problems.


    This page titled 0: Introductory Geometry was last modified on Tue, 03 Nov 2026 01:57:24 GMT and is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Leslie Shults.