Question

Car 1 drives 45 mph to the west, and car 2 drives 30 mph to the east. From the frame of reference of car 1, what is the velocity of car 2?

Answer 1

Use:\[\huge v_{2/1}=v_2-v_1\]Where,
\(v_{2/1}\) is the velocity of car 2 with respect to car 1
\(v_2\) is the velocity of car 2
\(v_1\) is the velocity of car 1

Answer 2

Keep in mind that you will need to establish a sign convention. That is, which way is positive and which is negative.