How do find the displacement when it is =ing to distance

[1/2"]

How do find the displacement when it is =ing to distance!

I am new here ,so please bear with me by helping in this simple problem
Problem:A ball moes on ta smooth floor in a straight line with uniform velocity 10meters/seconds for 6seconds.At t=6seconds, the ball hits a wall and comes back along the same line to the starting point with same speed.Draw the velocity -time graph and use it to find the total distance traveled by the ball and its displacement.
My try:
I had tried to make rough graph but the problem is that it is not coming displacement as 0
Because if velocity =10m/s & time=12(total time after returning)
.: displacement=v*t=10*12=120
But as it comes back to its original place ,I don't understand , How does it happen ?&
How do I represent it?
.Plz can anyone clear the consepts ?!

 

[CompuChip]

Hint: velocity, apart from a magnitude, also has a direction.

 

[1/2"]

THANKS A LOT CompuChipip!
I think I got the answer, as there is a negetive velocity due to moving back of the ball.:
It appears like this
|V
|
| __________
| .
| .
| .
|0_________ 6_________12______ (i don't know but the image is not coming correct)
| . . T
| . .
| . .
| .__________.
|V'
So,total area=(10*6)+(-10*6)=60-60=0=displacement!I am sooo happy!
Thanks million for ur help!Keep helping!

 

[CompuChip]

|V
|
| __________                              
|           .                
|           . 
|           .
|0_________ 6_________12______       
|           .          .           T
|           .          .
|           .          .
|           .__________.
|V'

Yep, exactly right! :)