Question

Point B is located between points A and C, AB= X^2-10, BC= 2X +2 and AC= 16 ,solve for X

Answer 1

Drawing a picture would be helpful.
So you have AB and BC, and AC is ALL of AB and BC. In other words, 
AC = AB+BC.
Now plug in what the problem gave you.
(16) = (x^2 -10) + (2x + 2)
16 = x^2 + 2x - 8
0 = x^2 + 2x -24
0 = (x+6)(x-4)
x = -6, 4