Reflection: Real World Applications Are x and y Directly or Inversely Proportional? (Day 1 of 2) - Section 3: Exit Slip


As an application of Direct Variation, there is an online article about Leonardo Da Vinci and how body parts are directly proportional.  If time permits, I assign the students this article to read and 2 problems to work with their table partner. 

I demonstrate setting up the proportions to the problems in this video:

Web source: (accessed November 26 2013)

  Extension of a Direct Variation Application
  Real World Applications: Extension of a Direct Variation Application
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Are x and y Directly or Inversely Proportional? (Day 1 of 2)

Unit 3: Linear Functions
Lesson 12 of 20

Objective: SWBAT recognize and describe Direct Variation using multiple representations and solve for the Constant of Variation (k).

Big Idea: This lesson introduces students to Direct Variation by comparing the equation y=kx to the now familiar equation y=mx + b.

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3 teachers like this lesson
Math, Math, warm up, collaborative activity, frayer model, graphic organizer, exit ticket, power point on inverse variation and direct variation, slope intercept form y=mx + b, y=kx, y=k/x
  50 minutes
direct variation image
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