$$ \begin{flalign*} & \textbf{Aufgabe} & \\ a) \\12 X + 12 = 6 \\ b) \hspace{1cm} & \6 X + 11 = 6 \\ c) \hspace{1cm} & \3 X + 9 + -21 = 10 - 9 X \\ d) \hspace{1cm} & \6 X + 8 = -29 \\ e) \hspace{1cm} & \8 X + 8 -29 = 8 X + 8 -29 \\ f) \hspace{1cm} & \5 X + 8 = -29 + -29 X \\ h) \hspace{1cm} & \8 X + 8 + 2X - -29 = 8 X + 8 -29 X + 6 \\ \end{flalign*} $$