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Mechanics - Motion with constant Acceleration - Immediate help Needed

Two particles, X and Y, are moving on parallel horizontal tracks. At time t=0 both particles pass O (a fixed point). Both particles moves to the left of O. Velocity of X = 3 m/s and Acceleration of X = 5 m/s^2.
Velocity of Y = 7 m/s and Acceleration of Y = 2 m/s^2.

FIND;-
(1) the velocity of Y at the instant when X changes direction of motion.
My answer is 8.2 m/s. I found that X changes direction when t=(3/5) seconds.

(2) the time that elapses, from t=0, before both particles have the same velocity.
My thoughts:
I tried to sketch a velocity time graph for both particles. I guess for the two particles to have the same velocity, they should intersect. But then, particle Y is moving to the left and particle X to the right(changes direction of motion).

I solved for t by equating 2 equations. 3+5t = 7+2t , t = (4/3) but answers says (10/3) seconds.
I can't figure it out.

(3) the time that elapses from t=0, before X overtakes Y ???????????????????????


Please share all your valuable inputs/ideas.

THANKS IN ADVANCE.

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