A Toyota of mass 1500 kg is driving at 15 m/s North when it rear-ends a Cadillac of mass 2500 kg also moving North at 9 m/s. (The driver of the Toyota was probably texting) After the collision, the Toyota bounces back at 2 m/s. What is the speed of the Cadillac after the collision?

initial momentum = 1500*15+2500*9

final momentum = -1500*2 + 2500 x

initial = final :)
15*15+25*9 = 25x - 30

25 x = 225+30+225 = 480
x = 19.2
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check
45,000 = 45,000 ok