ANSWER
[tex]\begin{equation*} 12\text{ }kN \end{equation*}[/tex]
EXPLANATION
We want to find the reaction force at point A.
To do this, let us take the moment about point E. The sum of the moments about point E must be equal to 0:
[tex]\sum M_E=0[/tex]
Therefore, taking the moments of the given forces:
[tex]\begin{gathered} (A_x*1.5)-(3*2)-(3*(2+2))=0 \\ 1.5A_x-6-12=0 \end{gathered}[/tex]
Solve the equation for Ax:
[tex]\begin{gathered} 1.5A_x=6+12=18 \\ A_x=\frac{18}{1.5} \\ A_x=12\text{ }kN \end{gathered}[/tex]
That is the answer.
