# Algebraic Expressions Lesson 4 Episode 4 (Teachers)

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The students apply their method for finding the ending location for a scooter trip that starts at 4 meters and lasts for 3 seconds to two more trips with different velocities.

### Episode Supports

Focus Questions

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

1. [Pause the video at 0:39] Ask students to predict Hector’s end location for a ride that begins at 4 meters, takes 3 seconds, and has a velocity of 2.5 meters per second. Then ask them to find the actual end location and compare their work with ET and Haleemah’s.
2. [Pause the video at 3:26] If you plan to use the Supporting Dialogue prompt below, finish that before asking this question. Ask students to predict where Hector will end up after taking a scooter ride that starts at 4 meters, lasts for 3 seconds, and with a velocity of –2.5 meters per second. Then ask them to find the actual end location and compare their work with ET and Haleemah’s.

Supporting Dialogue

ET and Haleemah calculate that Hector’s end location for a ride that starts at 4 meters, lasts 3 seconds, and has a velocity of 2.5 meters per second would be 11.5 meters. At 3:26 they begin calculating Hector’s end point for a similar ride except for the velocity, which is –2.5 meters per second. Ask your students to discuss the conjecture of a (fictional) student, Frankie, who said that since the velocity is the same as before, just negative, then Hector’s end location should be –11.5 meters. Ask students to discuss what they think about Frankie’s conjecture with their partners and then share out with the whole class.