Geometry, Teacher\'s Edition

(Axel Boer) #1

  • Prove theorems about proportions.

  • Recognize true proportions.

  • Use proportions theorem in problem solving.


II.ProblemSolvingActivity-ProportionalTeamwork



  • For this activity, students are going to draw two proportional triangles.

  • Be sure to include measurements for each side of each triangle.

  • Then, when instructed, students are going to pass the triangles to the person to their right. The person on the
    end of the room passes across the room to the “first”person.

  • Then each person must write one proportion that represents the two triangles.

  • Then they pass them again.

  • Once again this repeats and the next student writes one proportion about the two triangles.

  • Now there are two proportions on the paper under the triangles.

  • Next it is passes again, and the last student writes the one remaining proportion.

  • Finally, it is given back to the starting person (who drew the triangles).

  • That student needs to correct the work of the other three.

  • This student needs to write at least one theorem that is represented by these proportions and explain why
    he/she selected that theorem.


III.MeetingObjectives



  • Students will prove theorems about proportions.

  • Students will recognize true proportions.

  • Students will use proportions theorem in problem solving.


IV.NotesonAssessment



  • Collect all student work at the end of the class.

  • First, check the triangles. Are they proportional?

  • Next, check all of the proportions that were written about the triangles.

  • Finally, check the notes/corrections and the theorem used.

  • Is it explained well?

  • Is it correct?

  • Provide students with feedback and comments.


Similar Polygons


I.SectionObjectives



  • Recognize similar polygons.

  • Identify corresponding angles and sides of similar polygons from a statement of similarity.

  • Calculate and apply scale factors.


II.ProblemSolvingActivity-Let’sGoFlyaKite-PartTwo



  • For this activity, students are going to revisit the work they did on kites.

  • Particularly, students are going to use their work on creating kite designs from pg. 398-399.

  • Ask students to identify what makes these kites similar. Brainstorm a list and write them on the board.


5.7. Similarity

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