Big Idea:

Big Idea 5

SSS, SAS, and ASA are sufficient criteria to justify triangle congruence.

1 week

Evidence of Understanding

  • justify the minimum requirements that show two triangles are congruent
    • describe how a sequence of transformations demonstrates the mapping of corresponding sides for two congruent figures
      • use notations to signify the corresponding parts
    • make conjectures about the minimum corresponding parts of the triangle needed to construct a congruent triangle
      • experiment with constructions to support these claims
      • give examples, non examples, or counterexamples about these claims
      • use transformations of these parts to support their claim that the triangles are congruent
    • justify that when all corresponding sides of two triangles are congruent (SSS) there is sufficient evidence to show that these two triangles are congruent
      • use tools to construct a copy of a given triangle using side measurements
    • justify that when two corresponding sides and the included angle are congruent (SAS) there is sufficient evidence to show that these two triangles are congruent
      • use tools to construct a copy of a given triangle using two side measurements and the included angle
      • establish the the minimum criteria necessary to prove two right triangles are congruent using the hypotenuse and a leg (HL)
    • justify that when two corresponding angles and the included side of two triangles are congruent (ASA) there is sufficient evidence to show that these two triangles are congruent
      • use tools to construct a copy of a given triangle using two angle measurements and the included side
      • justify why the angle has to be the included angle of the corresponding sides using constructions (SSA does not work)

Develop conceptual understanding:

SSS, SAS, HL, ASA

Supporting terms to communicate:

included angle/side, construct, copy, corresponding parts, preserve, congruent, sequence of transformations, rotate, reflect, translate, parallel, perpendicular
Core Resource
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    Instructional Routine: Contemplate then Calculate
    These tasks are embedded within the instructional routine called Contemplate then Calculate. COMING SOON!