sonom, 2014年3月16日

• 1. congruent triangles
• 2. equilateral triangle (SAS)
• 3. median to the hypotenuse
• 4. triangle midpoint theorem
• 5. angle bisector as locus
• 6. equal chords
• 7. chords and tangents
• 8. the outer Napoleon triangle
• 9. five squares