A = (1, 4)
B = (4.54, 4.8)
u = Vector(A, B)
C = (1, 3)
v = Vector(C, Translate[C, u])
D = (1, 2)
w = Vector(D, D + u)

Tool: vtNrMult
Input: A, u, a
Output: v

v = Vector(A, Translate[A, a * UnitVector[u]])