Решебник по алгебре 9 класс Макарычев Задание 556

 

\[\boxed{\text{556\ (556).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[|x| + |y| \leq 1;\]

\[1)\ x \geq 0,\]

\[y \geq 0 \Longrightarrow x + y \leq 1,\]

\[y \leq 1 - x;\]

\[2)\ x \leq 0,\]

\[y \geq 0 \Longrightarrow - x + y \leq 1,\]

\[y \leq 1 + x;\]

\[3)\ x \leq 0,\]

\[y \leq 0 \Longrightarrow - x - y \leq 1,\]

\[y \geq - x - 1;\]

\[4)\ x \geq 0,\]

\[y \leq 0 \Longrightarrow x - y \leq 1,\]

\[y \geq x - 1.\]

\[\boxed{\text{556.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]

\[x_{n} = x_{1} + d(n - 1)\]

\[x_{16} = - 7;\ \ x_{26} = 55:\]

\[\left\{ \begin{matrix} x_{1} + 15d = - 7 \\ x_{1} + 25d = 55 \\ \end{matrix} \right.\ \Longrightarrow\]

\[\Longrightarrow \left\{ \begin{matrix} 10d = 62\ \ \ \ \ \ \ \ \ \\ x_{1} = - 7 - 15d \\ \end{matrix} \right.\ \Longrightarrow\]

\[\Longrightarrow \left\{ \begin{matrix} d = 6,2\ \ \ \ \ \ \ \\ x_{1} = - 100. \\ \end{matrix} \right.\ \]

\[Ответ:d = 6,2;\ \ x_{1} = - 100.\]