Congruent Triangles by SSS, SAS, ASA, AAS, and HL - Practice / Review:
This activity includes three parts that can be done all in one lesson or spread out across a unit on congruent triangles. You can print the two sets of “Triangle Cards” for worksheets A and C on colored cardstock if desired. These pieces can also be laminated and re-used in learning stations if you wish.
In Worksheet A, students match up the attached “Triangle Cards” to practice identifying SSS, SAS, ASA, AAS, and HL. They also find that the pair leftover (SAA) are not necessarily congruent. Students must write the triangle congruence statement correctly for the corresponding parts.
In Worksheet B, students begin to develop the thought process that they will need for writing triangle congruence proofs. They must identify the “given” information from the diagrams and then come up with their own congruence statements for parts that they determine are congruent. They also must justify their reasoning. This sheet has diagrams containing two triangles so that students get used to seeing the types of diagrams that appear in proofs.
In Worksheet C, students again have to match the diagrams on the cards along the correct type of congruent triangles (SSS, SAS, ASA, AAS, and HL). The leftover diagram contains an AAA situation, and therefore students must recognize that this does not assure congruency. On this page, in addition to triangle congruence statements, students write congruence statements for each of the parts of the triangles. (This can help them to later succeed with CPCTC proofs.)
*** Note: This activity is also included in a larger DISCOUNTED bundle:
Try these related resources as you begin proofs:
Proofs: Full Unit
Geometry Proofs Task Cards