`a) 6,5 - 9/4 ÷ |x + 1/3| = 2`
`9/4 ÷ |x + 1/3| = 6,5 - 2`
`9/4 ÷ |x + 1/3| = 3,5`
`|x + 1/3| = 9/4 ÷ 3,5`
`|x + 1/3| = 1/2`
$\left[\begin{matrix} x+1=1/2\\ x-1=-1/2\end{matrix}\right.$
`⇔`$\left[\begin{matrix} x=1/6\\ x=-5/6\end{matrix}\right.$
`b) 11/4 + 3/2 ÷ |4x - 1/5| = 7/2`
`3/2 ÷ |4x- 1/5| = 7/2 - 11/4`
`3/2 ÷ |4x - 1/5| = 3/4`
`|4x - 1/5| = 3/2 ÷ 3/4`
`|4x - 1/5| = 2`
$\left[\begin{matrix} 4x-1/5=2\\ 4x-1/5=-2\end{matrix}\right.$
`⇔`$\left[\begin{matrix} 4x=11/5\\ x-1=-9/5\end{matrix}\right.$
`⇔`$\left[\begin{matrix} x=11/20\\ 4x=-9/20\end{matrix}\right.$