Geometry/Similar Triangles

For two triangles to be similar, all 3 corresponding angles must be congruent, and all three sides must be proportionally equal. Two triangles are similar if...

• Two angles of each triangle are congruent.
• The acute angle of a right triangle is congruent to the acute angle of another right triangle.
• The two triangles are congruent. Note here that congruency implies similarity.

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• Geometry
• Part I- Euclidean Geometry:
  • Chapter 1. Geometry/Points, Lines, Line Segments and Rays
  • Chapter 2. Geometry/Angles
  • Chapter 3. Geometry/Properties
  • Chapter 4. Geometry/Inductive and Deductive Reasoning
  • Chapter 5. Geometry/Proof
  • Chapter 6. Geometry/Five Postulates of Euclidean Geometry
  • Chapter 7. Geometry/Vertical Angles
  • Chapter 8. Geometry/Parallel and Perpendicular Lines and Planes
  • Chapter 9. Geometry/Congruency and Similarity
  • Chapter 10. Geometry/Congruent Triangles
  • Chapter 11. Geometry/Similar Triangles
  • Chapter 12. Geometry/Quadrilaterals
  • Chapter 13. Geometry/Parallelograms
  • Chapter 14. Geometry/Trapezoids
  • Chapter 15. Geometry/Circles/Radii, Chords and Diameters
  • Chapter 16. Geometry/Circles/Arcs
  • Chapter 17. Geometry/Circles/Tangents and Secants
  • Chapter 18. Geometry/Circles/Sectors
  • Appendix A. Geometry/Postulates & Definitions
  • Appendix B. Geometry/The SMSG Postulates for Euclidean Geometry

• Part II- Coordinate Geometry:
  • Geometry/Synthetic versus analytic geometry

• Two and Three-Dimensional Geometry and Other Geometric Figures
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  • Geometry/Right Triangles and Pythagorean Theorem
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  • Geometry/Area Shapes Extended into 3rd Dimension Linearly to a Line or Point
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  • Geometry/Coordinate Systems (currently incorrectly linked to Astronomy)

• Traditional Geometry:
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• Modern geometry
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• Geometry/An Alternative Way and Alternative Geometric Means of Calculating the Area of a Circle