Exponentials Lesson 4 Episode 4 (Teachers)

Repeating Your Reasoning

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The students use their timeline to create an equation that gives the height of the new beanstalk on any day.

Episode Supports

Focus Questions

For use in a classroom, pause the video and ask these questions:

  1. [Pause the video at 0:16] Create an equation that gives the height of the beanstalk on any day, assuming the beanstalk starts out as 2 cm tall on Day 0. As you watch the video, compare your equation to the one that Arobindo and Josh create.
  2. [Pause the video at 0:43] Examine the equation 2 × 3n = p. What does each component of the equation represent in the context of the growing beanstalk?

Supporting Dialogue

At [1:25] Josh says that the expression 3n represents the growth factor from Day 0 to Day n. Ask your students to first explain what they think Josh means by this claim. Then ask them to discuss with a partner if they think the expression 3n could represent the growth factor between a different pair of days.