Idon’t know where to start and what variables i’ll need to get to the answer.

4 seconds

Explanation:

Start with this observation: the distance traveled by car A, plus the distance traveled by car B, plus the original 15 meter gap, equals the 55 meter separation at time t.

dA + dB + 15 = 55

You're given the equation for distance traveled at constant acceleration when the initial velocity is 0:

d = 0.5at²

Given that the acceleration of car A is 2 m/s² and the acceleration of car B is 3 m/s², all you have to do is plug in the expressions and variables and solve for t.

0.5 (2) t² + 0.5 (3) t² + 15 = 55

t² + 1.5 t² = 40

2.5 t² = 40

t² = 16

t = 4

answer: pseudoscience

d.7.5cm is your answer