- Naming triangles and angles using the three vertex method
- Stating triangle congruences by naming vertices in the corresponding order
- Marking congruent segments and angles using one, two, or three tick marks
- Distinguishing AAS from ASA and SAS from SSA by identifying included sides/angles
To teach these skills, I've created my version of a perfect 9th grade proof below: I would like to have students label each Side and Angle in their proof and also mark up the diagram with congruent and parallel marks, as well as check that shapes are named correctly. I'm also toying with the idea of them having to write the triangle congruence statement for themselves.