Determine inverse matrices

$A=\left[\begin{array}{rr} 4 & -3 \\ 18 & -9 \end{array}\right] $ and $B=\left[\begin{array}{rr} -\dfrac{1}{2} & \dfrac{1}{6} \\\\-1 & \dfrac{2}{9} \end{array}\right]$ **Are $A$ and $B$ inverses?** [[☃ radio 1]]