friction problem

A car travelling at an initial velocity $$v_{0}$$ applies its brakes to come to a stop. The coeffictien of friction is $$\mu$$. What distance is required to stop?

I know that you can solve for x using this equation:
$$v^2=v_{0}^2+2ax$$

-but i don't know how to solve for acceleration a. any help?
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 Blog Entries: 1 Recognitions: Homework Help Can you calculate the frictional force? If so, can you calculate the acceleration, by, say, using the definition of force? Try it out, assigning the mass to be m0, and see what you get
 Im trying to do a force balace to find a but im not sure this is right. $$-\mum_{0}g=m_{0}a$$ solving for for a, i get $$a=\mug$$