Assuming north is upwards in this coordinate plane, if the fire department is in point (4, -3), it is in the coordinates x = 4 and y = -3, so if the police department is located 5 blocks north from it, we can find its location by adding 5 to its y coordinate.
The y coordinate is -3, so adding 5 we get:

Since we didn't change its location for the sides, the x coordinate is the same.
So, the police department is in x = 4 and y = 2, so it is in point (4, 2).