For this case the equation of movement is given by:
[tex] vf = a*t + vo [/tex]
Where,
vf: final speed
a: acceleration
t: time
vo: initial speed
Clearing the acceleration we have:
[tex] a =\frac{vf - vo}{t} [/tex]
Substituting values:
[tex] a =\frac{12 - 6}{2} [/tex]
Rewriting:
[tex] a =\frac{6}{2}[/tex]
[tex] a=3 [/tex]
Answer:
your acceleration is:
[tex] a = 3\frac{m}{s^2}[/tex]