If $x=\large\frac{2}{3}$ and $x=-3$ are the roots of the equation $ax^2+7x+6=0$,then the values of $a$ and $b$ are ________

Question

$(A) \;a=-3,b=6\\(B)\;a=-3,b=-6\\(C)\;a=3,b=-6\\(D)\;a=3,b=6$