(In this question the answer is -4, please explain how did they get it)
If A and B have coordinates -15 and 11, what is the coordinate of X if X is 4 units farther from B as from A?
Always make a sketch
Place X between A and B , a bit closer to A
XB - XA = 4
11-x - (x-(-15)) = 4
11-x - x - 15 = 4
-2x = 8
x = -4
check by counting the result on the number line