Calculating Average Velocity for a Car with Changing Acceleration and Direction

[jelly1500]

[SOLVED] acceleration and velocity

1. Homework Statement
EXACT PROBLEM:
A car accelerates from rest W at 5.0m/s2 for 10.0s, then continues this acceleration NE for another 10.0s. What is the average velocity of the car for its journey to its position after 20.0s? 2. Homework Equations
average velocity=average displacement/time
Delta x=Vit + 1/2at^2
Vf=Vi+at

3. The Attempt at a Solution
First, I found Delta x and Vf for the west vector than found Delta x for the NE vector. Then I tried to find the displacement using Pythagoreans theorem but it was not the correct answer.

 

[Doc Al]

A car accelerates from rest W at 5.0m/s2 for 10.0s,

Where's the car after 10 s?

then continues this acceleration NE for another 10.0s.

Now where is it? What's the total distance displacement from the origin?

 

[jelly1500]

after the first 10 sec., its 250 meters away, then after the second 10 sec., its 750 meters

 

[Doc Al]

What's the exact location?

 

[jelly1500]

oh, I get it! I'm supposed to break in down into it's x and y components. Thank you so much!