Two dimensional acceleration question

[F.B]

My book stinks it doesn't explain or show you how to do enough examples. But anyways i have another problem now. I figured out how to do my other question. Anyways my question is...

A car with a velocity of 25 m/s [E] changes its velocity to 25 m/s in 15s. Calculate the car's average acceleration.

How do i start this question off. I don't know what to do.

 

[2Pac]

Are we looking for a magnitude of acceleration or a vector form?

 

[F.B]

the magnitude and degrees/direction

 

[Doc Al]

Use the definition of average (vector) acceleration:
\vec{a}_{ave} = \frac{\Delta \vec{v}}{\Delta t}

(Hint: To find the change in the velocity, write the initial and final velocity in component form and then subtract.)