Parabolas Lesson 2 Episode 4 (Teachers)

Keoni and Sasha extend their use of the Pythagorean theorem. They determine the x-value for a point on the parabola that has a y-value of 5.

Focus Questions

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

1. [Pause video at 0:41]. Sasha drew a horizontal line. What is the true about every point on that line?

2. [Pause video at 2:24]. Keoni says that the value of b is 5.29. Are there other possibilities for a value for b so that b² will equal 28?

Supporting Dialogue

Invite your students to reflect on the emergence of a mathematical method by asking:

1. Summarize your methods to find the x-value of a point on the parabola with a y-value of 7.

2, Will these methods always work? Why?

Math Extensions

1. Solve for the x-value of a point on the parabola with a y-value of ½.

2. 1. Solve for the x-value of a point on the parabola with a y-value of √10.