ГДЗ по алгебре 8 класс Мерзляк Задание 740

\[\boxed{\mathbf{740\ (740).\ }Еуроки\ - \ ДЗ\ без\ мороки}\]

\[1)\ x² + bx + 6 = 0\]

\[x_{1} \cdot x_{2} = 6\]

\[x_{1} + x_{2} = - b\]

\[x_{1} = 6,\ \ x_{2} = 1,\ \ - b = 7,\ \ \]

\[b = - 7\]

\[x_{1} = - 6,\ \ x_{2} = - 1,\ \ \]

\[- b = - 7,\ \ b = 7\]

\[x_{1} = 3,\ \ x_{2} = 2,\ \ - b = 5,\]

\[\ b = - 5\]

\[x_{1} = - 3,\ \ x_{2} = - 2,\ \ \]

\[- b = - 5,\ \ b = 5\]

\[Ответ:\ при\ b = - 7;7;\ b = - 5;5.\]

\[2)\ x² + bx - 12 = 0\]

\[x_{1} \cdot x_{2} = - 12\]

\[x_{1} + x_{2} = - b\]

\[x_{1} = - 12,\ \ x_{2} = 1,\]

\[b = 11\]

\[x_{1} = - 1,\ \ x_{2} = 12,\]

\[b = - 11\]

\[x_{1} = 6,\ \ x_{2} = - 2,\ \ b = - 4\]

\[x_{1} = - 6,\ \ x_{2} = 2,\ \ b = 4\]

\[x_{1} = - 4,\ \ x_{2} = 3,\ \ b = 1\]

\[x_{1} = - 3,\ \ x_{2} = 4,\ \ b = - 1\]

\[Ответ:при\ b = 11;\ - 11;\ \]

\[b = - 4;4;b = 1;\ - 1.\]