\[\boxed{\mathbf{986\ (986)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\textbf{а)}\ \mathrm{\Delta}ABC.\]
\[\textbf{б)}\ \mathrm{\Delta}DEF.\]
\[\text{D\ }( - 6; - 2);\ \ E( - 2; - 2);\ F\ ( - 2; - 4).\]
\[\textbf{в)}\ \mathrm{\Delta}KLM.\]
\[\text{K\ }(6;2);\ \ L\ (2;2);\ \ M\ (2;4)\text{.\ }\]