What is the final speed of the probe?

A 6.5 104 kg space probe is traveling at a speed of 13000 m/s through deep space. Retrorockets are fired along the line of motion to reduce the probe's speed. The retrorockets generate a force of 5.0 105 N over a distance of 2400 km. What is the final speed of the probe?|||force= mass X acceleration. you have mass of the probe and the force of the rockets, find the acceleration. now its linear kinematics, you have initial speed, acceleration, and displacement. Vf^2=Vo^2 + 2ax seems like a nice formula to use here