Proving Theorems involving Similar Triangles

Unit 6: Similarity
Lesson 5 of 8

Objective: SWBAT prove that a line parallel to a side of a triangle divides the other two sides proportionally, and conversely.

Big Idea: 9 steps for one and 3/4 of a dozen for the other. In this lesson students will learn to write two 9-step proofs that involve similar triangles.

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Subject(s):
Math, similar triangles, Triangle proportionality theorem
  75 minutes
partition segment construction
 
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