\[\boxed{\mathbf{791\ (791)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\textbf{а)} - 10 \bullet x = 70\]
\[x = 70\ :( - 10)\]
\[x = - 7.\]
\[Ответ:x = - 7.\]
\[\textbf{б)}\ x \bullet ( - 12) = - 24\]
\[x = - 24\ :( - 12)\]
\[x = 2.\]
\[Ответ:x = 2.\]
\[\textbf{в)} - 8 \bullet x = 64\]
\[x = 64\ :( - 8)\]
\[x = - 8.\]
\[Ответ:x = - 8.\]
\[\textbf{г)}\ \ x \bullet ( - 4) = - 20\]
\[x = - 20\ :( - 4)\]
\[x = 5.\]
\[Ответ:x = 5.\]