Answer:
x = 12
Explanation:
Given that AB = 2, AD = x, BC = 2, CD = -16 + 2x, since A, B, C, D are said to be collinear, therefore:
AB + BC + CD = AD
2 + 2 + (-16 + 2x) = x
Use this equation to solve for x
2 + 2 - 16 + 2x = x
-12 + 2x = x
Subtract 2x from both sides
-12 + 2x - 2x = x - 2x
-12 = -x
Divide both sides by -1
12 = x (negative cancels negative)
x = 12