The position of a point B in the coordinate plane is:
B(-1 , -4)
In order to find the position of B after a translation of (x + 2 , y - 3) , you simply add 2 units to x coordinate and subtract 3 units to the y coordinates, just as folow:
B(-1,-4) => B'( -1 + 2 , -4 - 3) = B'(1 , -7)
Hence, the position of B after the translation is B'(1,-7)