This page is about using principles and theorems to solve steps in geometry problems, and to justify those steps.
30-60-90 Triangle Part 1:
Principles 1,2,3:
Principles 5,6,7:
Principle 8 (Transversals):
Principle 9 (Right Triangle) Example 1:
Principle 9 (Right Triangle) Example 2:
Principle 11 (Triangle):
Principle 12:
Principle 13:
Principle 14:
Principle 16 (Trapezoid) Example 1:
Principle 16 (Trapezoid) Example 2: