Based on the data, the students in Mr. Lastorka’s class determine the exact equation
involving Watts, x, and total distance from start, y. They call the function y = f(x). Mr.
Lastorka then instructs his class to reflect y = f(x) over the x-axis. He challenges each
student to determine the new function and what it would mean from a physics perspective.
Four student pairs gave their answers below. Who is correct, and for what reasons?
A) Charles and Shannon, who identify the new equation as y = –2x and explain that the
new graph indicates that the car is still moving forward at the same rate as before.
B) Michael and Lauren, who identify the new equation as y = –2x and explain that the
new graph indicates the car is now moving in reverse at the same rate as before.
C) Matthew and Karen, who identify the new equation as y = 2–x and explain that the
new graph indicates that the car is now moving forward more rapidly than before.
D) Andy and Joanie, who identify the new equation as y = 2–x and explain that the new
graph indicates that the car is no longer moving in any direction.