Question

решите пжпжпжппжпжпж.токо (B и Г) дам 50балов срочно ООО!!!!!!!!!!?!!!!!?!!!!??????!!!!​

Answer 1

Ответ:

Пошаговое объяснение:

В.

$\displaystyle\\\[\begin{gathered} \left\{ \begin{gathered} x = - 8 \hfill \\ 4x - 8y = - 27 \hfill \\ \end{gathered} \right. \hfill \\ 4 \cdot ( - 8) - 8y = - 27 \hfill \\ - 36 - 8y = - 27 \hfill \\ - 8y = - 27 + 36 \hfill \\ - 8y = 9 \hfill \\ 8y = - 9 \hfill \\ y = - \frac{9}{8} = - 1\frac{1}{8} \hfill \\ \end{gathered} \]$

Г.

$\displaystyle\\\[\left\{ \begin{gathered} 7x + 7y = - 7 \hfill \\ 10x + 2y = - 5,2 \hfill \\ \end{gathered} \right.\]$

делим правую и левую часть первого уравнения на 7, получаем

$\displaystyle\\\[\begin{gathered} 7x + 7y = - 7(:7) \hfill \\ \left\{ \begin{gathered} x + y = - 1 \hfill \\ 10x + 2y = - 5,2 \hfill \\ \end{gathered} \right. \hfill \\ y = - 1 - x \hfill \\ 10x + 2 \cdot ( - 1 - x) = - 5,2 \hfill \\ 10x - 2 - 2x = - 5,2 \hfill \\ 8x - 2 = - 5,2 \hfill \\ 8x = - 5,2 + 2 \hfill \\ 8x = - 3,2 \hfill \\ x = - 3,2:8 \hfill \\ x = - 0,4 \hfill \\ y = - 1 - x = - 1 - ( - 0,4) = - 1 + 0,4 = - 0,6 \hfill \\ \end{gathered} \]$