The x axis is horizontal, and its coordinates increase rightwards. So, a translation left 1 unit has consequences on the x coordinate, and you must decrease it by 1.
The y axis is vertical, and its coordinates increase upwards. So, a translation up 4 unit has consequences on the y coordinate, and you must increase it by 4.
The final result is thus
[tex](-1,-5)\mapsto(-1-1,-5+4)=(-2,-1)[/tex]
