Parabolas Lesson 7 Episode 6 (Teachers)


Download Math TaskLink to Geogebra applet

Sasha and Keoni use what they know about special points to explain why increasing the p-value results in the parabola getting wider on the coordinate grid.

Episode Supports

Focus Questions

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

1. [Pause video at 1:06]. What are Sasha and Keoni saying about the coordinates of a special point on the parabola? Do you agree? Why or why not?

2. [Pause video at 2:36]. Keoni says “it increases more.” What is increasing more?

Supporting Dialogue

Provide opportunities for students to revoice a mathematical proposition. Ask a few students to revoice the proposition of this episode:

Revoice Keoni and Sasha’s proposition that uses the special point to explain why increasing the p-value results in a wider parabola on the coordinate grid.

Math Extensions

1. In this lesson, several arguments are made to justify why increasing the p-value results in a change in the width of the parabola. Write down each of these justifications.

2. How are the arguments similar? How are they different? Do you prefer one justification more than another? Explain.