Parabolas Lesson 9 Episode 5 (Teachers)

Reflecting

Download Math Task

Sasha and Keoni look back on their work with a parabola with a p-value of 5 and a vertex of (9, 13). By reflecting on their work and the equation y = (x – 9)2/(4p) + 13, they see 13 their graph.


Episode Supports

Focus Questions

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

1. [Pause the video at 1:13]. Where is the 8 in the graph? Does any one see the 13 in the graph? Where is it?

2. [Pause the video at 1:43] Can someone show me the 13 in the graph? How do you know that it is 13?

Supporting Dialogue

Invite students to engage in a pair-share activity as they respond to the focus question:

1. With your partner, show where you can find 13 on the graph. Prepare your answers to share with the whole class.

2. With your partner, extend your answer to find 13+p on the graph. Prepare your answers to share with the whole class.

Math Extensions

1.  What expression is easier for you to simplify? How are they different to you? How are they the same?

(y – 13 – p)2
(y – (13 + p))2
((y – 13) – p)2

2. How are each of these expressions present in the Sasha and Keoni’s graph?