they have the same y coordinate, 8, so all we need to figure out is the distance between -12 and 2 of this horizontal line.
to do this add 12 and 2, you should get 14.
now using this information, find the expression that is equal to 14.
|-12|+|2|=14
|-12|-|2|=10
|8|+|8|=16
|8|-|8|=0
as we can see, the first expression would be the correct one.
