Question 1184510
Under the assumption the first equation has a misprint,
The given equations are as {{{system(y=(a/3)x-6,4x+2y=6)}}} .


{{{system(y=(a/3)x-6,2x+y=3)}}}


{{{system(y=(a/3)x-6,y=-2x+3)}}}


If perpendicular, then  {{{(a/3)(-2)=-1}}}
{{{(a/3)*2=1}}}
{{{highlight(a=3/2)}}}