Point-A is located at -2.
Point-B is located at 12.
The distance from -2 to 12 is [ 12 - (-2) ] .
That's 14 units.
Another way to think about it:
Point-A is 2 floors below ground.
Point-B is 12 floors above ground.
To get from A to B, you have to take the elevator up 14 floors. (2 + 12)