Q1,W9: October 8-12

TeacherKristin Andreason
Subject AreaGeometry Honors
Grade Level8
Week #Nine
Unit of InstructionUnit 2(A): Triangle Congruence and Proofs
Standard(s) Taught

MAFS.912.G-CO.1.3:  Given a rectangle, parallelogram, trapezoid, or regular polygon, describe the rotations and reflections that carry it onto itself.  

MAFS.912.G-CO.1.5:  Given a geometric figure and a rotation, reflection, or translation, draw the transformed figure.  Specify the sequence of transformations that will carry a given figure onto another.

MAFS.912.G-CO.2.8:  Explain how the criteria for triangle congruence (ASA, SAS, SSS, and HL) follow from the definition of congruence in terms of rigid motions.

MAFS.912.G-CO.3.10:  Prove theorems about triangles, use theorems about triangles to solve problems.

Learning Targets and Learning Criteria
  • Students will learn how to determine the reflections and rotations that will map a regular polygon onto itself.
  • Students will be able to calculate the number of lines of reflection symmetry and the degree of rotational symmetry of any regular polygon.
  • Students will be able to predict and verify the sequence of transformations (a composition) that will map a figure onto another.
  • Students will be able to identify the conditions to prove triangles are congruent.
  • Students will be able to demonstrate that AAA SSA do not prove triangle congruence.
  • Students will be able to classify triangles by sides and angles.
  • Students will be able to solve problems using theorems and postulates about triangles.
Classroom Activities


  • Students will do three rotations:  
    • They will finish the triangle congruence packet
    • They will copy notes on Classifying Triangles (p. 14) and do IXL-F.1
    • I will work with one group to go over the Formative Assessment they did and to practice more, including reflecting across the line y=x.


  • Students will take the Summative on Transformations


  • Students will take notes on the Angle Sum Theorem and do IXL-F.2
  • Students will take notes on the External Angle Theorem and do a Kuta Software worksheet to practice
  • Students will learn how to rotate a regular polygon onto itself and then do IXL-L.11 to practice
Assignments Due
  • IXL-F.1 is due by the end of class on Mon/Tues October 8/9.
  • Summative on Transformations is due by the end of class on Wednesday, October 10
  • Kuta Software worksheet on External Angle Theorem is due by end of class October 11/12
  • IXL-F.2 is due by Tuesday, October 16
  • IXL-L.11 is due by Tuesday, October 16.
Additional Resources

All IEP and ESOL accommodations will be provided daily.