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Triangles - Part I

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Summary
The content provides an in-depth exploration of fundamental properties and rules governing the geometry of triangles, essential for GRE exam preparation.
  • The sum of the three angles inside any triangle is exactly 180 degrees, a foundational geometric principle.
  • Triangles cannot have more than one right or obtuse angle, ensuring at least two angles are acute.
  • The largest angle in a triangle is always opposite the longest side, and the smallest angle is opposite the shortest side.
  • The Triangle Inequality Theorem states that the sum of any two sides of a triangle must be greater than the third side.
  • For any two sides of a triangle, the length of the third side must be greater than the difference and less than the sum of these two sides.
Chapters
00:01
Fundamental Properties of Triangles
01:05
Angles and Their Sum in Triangles
05:32
Triangle Inequality Theorem
09:13
Determining the Lengths of Triangle Sides

Quiz

Geometry (Not tested on Focus edition)