# Motion Distance-Time graphs

#### katelyn_1025

##### New member
hi,
Just wondering if you can have a negative distance on a distance time graph (a negative sloping line)?
also can you find displacement on a distance time graph?
Thanks

#### LCKurtz

##### Full Member
hi,
Just wondering if you can have a negative distance on a distance time graph (a negative sloping line)?
also can you find displacement on a distance time graph?
Thanks
I'm guessing you are confusing distance and position. If $$\displaystyle x(t)$$ is the position of an object at time $$\displaystyle t$$, then $$\displaystyle x(b) - x(a)$$ is the change in position from time $$\displaystyle a$$ to time $$\displaystyle b$$. This may be negative or positive depending on whether the object is moving in a positive direction. $$\displaystyle x(b) - x(a)$$ will be the distance traveled only if the object moved exclusively in the positive direction during that time. If the object ends up where it started, the change in position is $$\displaystyle 0$$, but you probably wouldn't want to say the distance traveled was $$\displaystyle 0$$.

#### LCKurtz

##### Full Member
To the moderator: Please stop with the delayed postings.

#### MarkFL

##### Super Moderator
Staff member
To the moderator: Please stop with the delayed postings.
Our administrator has configured the forum software settings such that users with less than a certain number of posts require their posts to be approved by the moderating staff. It is an anti-spam measure we have taken.