Each dot is worth -1/8 of a unit when moving left.
So the coordinates of the dark dot are - 1 and - 3/8
or - 1.375 . The word coordinates (plural) bothers me. It all depends on how you have been asked to represent these points. Another possibility is (-1.375,0). You have to choose from the examples you have been given. I wouldn't do that because you have not been given and xy graph.
