For \( \lambda, \mu \in \mathbb{R} \), the lines
\[
(x - 2y - 1) + \lambda (3x + 2y - 11) = 0
\]
and
\[
(3x + 4y - 11) + \mu (-x + 2y - 3) = 0
\]
represent two families of lines. If the equation of the line common to both families is given by
\[
ax + by - 5 = 0,
\]
then \( 2a + b = \) ?