# Q2, W3: November 1-5 Geometry Teacher Kristin Andreason Geometry Honors 8 November 1-5 Unit 2B: Congruence of Proofs with Triangle Properties
Standard(s) Taught

MAFS.912.G-CO.2.7: Use the definition of congruence in terms of rigid motions to show that two triangles are congruent if and only if corresponding pairs of sides and corresponding pairs of angles are congruent.

MAFS.912.G-SRT.2.5: Use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures.

Learning Targets and Learning Criteria
• Students will be able to determine whether or not two triangles are congruent by the Triangle Congruence Postulates (SSS, SAS, ASA, AAS, and HL)
• apply triangle congruence and triangle similarity to solve problems (e.g., indirect measure, missing sides/angle measures, side splitting).
• apply triangle congruence and triangle similarity to prove relationships in geometric figures.
• use CPCTC (Corresponding Parts of Congruent Triangles are Congruent) to find missing sides/angles AFTER triangles are proved congruent.
Classroom Activities

Monday/Tuesday:

1. Students will create a foldable on Triangle Congruence Theorems
2. We will examine why SSA and AAA do not prove congruence
3. We will do some practice examples together from the Let’s Practice Geometry packet
4. Students will do IXL K.5

Wednesday:

1. I will introduce proofs, how they work, etc.
2. We will do some examples together (Methods of Proof/Two Column Proofs document)
3. Students will do some practice on IXL K.7

Thursday/Friday:

1. Students will do the Triangle Congruence Proofs Activity
2. If they finish, they can work more on IXL K.7
Assignments Due
• IXL K.5
• Triangle Congruence Proofs Activity