If A, B and C are collinear, then
1) if B is between A and C:
AC = AB + BC
AC = 48 + 22 = 70
2) if C is between A and B:
AB = AC + BC
48 = AC + 22 |-22
AC = 26
3) if A is between B and C:
BC = AB + AC
22 = 48 + AC |-48
AC = - 26 < 0 FALSE
Answer:
if B is between A and C, then AC = 70
if C is between A and B, then AC = 26
The answer to this is 7.5.