Triangles

Triangles

1. 3 Angles

   • Acute: The angle is under 90º
     • Acute Triangle: 3 Acute Angles
     • Equilangular Triangle: 3 Congruent Acute Triangles
   • Right: The angle is 90º
     • Right Triangle: 1 Right Triangle
   • Obtuse: The angle is over 90º
     • Obtuse Triangle: 1 Obtuse Triangle

2. 3 Sides

   • Equilateral Triangle: All 3 Sides are Congruent
   • Isoceles Triangle: 2 Sides are Congruent
   • Scalene Triangle: No Sides are Congruent

3. Congruency: The same size

   • SSS
     • SAS
       • ASA
   • AAS

4. Triangle Angle Sum Theorem

   • A+B+C=180
   • Interior Angles: Angles Within The Triangle
   • Exterior Angles: Angles Outside of The Triangle

5. Vertex Angle: Angle Formed by The Legs

6. Base Angle: 2 Angles Formed on The Base

7. Transformations

   • Reflection: The Shape Flips In a Certain Direction
   • Rotation: Movement Of The Shape in Accordance to a Certain Point
   • Translation: Simple Movement

8. Bisectors: Line That Divides an Angle Into 2 Congruent Sides

   • Median: The Endpoints Are On The Vertex and The Midpoint is On The Opposite Side
   • Centroid: The Point Of Concurrence
   • Altitude: Segment That Goes From The Vertex To The Opposite Side
     • Orthocenter: Point Where All Altitudes Intersect

9. Inequalities in Triangles

   • The Sum Of The Legths of Any 2 Sides Of a Triangle Must Be Greater Than The Lengths of The 3rd Side