 \overline{ a } 

t\bar{a}=\bar{0}

A = (4, 4)
B = (6, 5)
u = Vector(A, B)
t = 1 (slider from -5 to 5, step 0.5)
v: (t * u)
C = Midpoint(A, B)
D = (9, 1)
D' = Translate(D, v)
w = Vector(D, D')
E = Midpoint(D, D')
teksti2: "t\overline{ a }   \; =  \;  " + (LaTeX[t]) + "\overline{ a }"