ГДЗ по алгебре 7 класс Макарычев ФГОС Задание 907

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\[\textbf{а)}\ m² - 25 = 0\]

\[(m - 5)(m + 5) = 0\]

\[m = 5\ \ или\ \ \ m = - 5\]

\[Ответ:m = \pm 5.\]

\[\textbf{б)}\ x² - 36 = 0\]

\[(x - 6)(x + 6) = 0\ \]

\[x = 6\ \ \ или\ \ \ \ x = - 6\]

\[Ответ:x \pm 6.\]

\[\textbf{в)}\ 9x² - 4 = 0\]

\[(3x - 2)(3x + 2) = 0\]

\[3x = 2\ \ \ или\ \ \ \ 3x = - 2\]

\[x = \frac{2}{3}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x = - \frac{2}{3}\]

\[Ответ:x = \pm \frac{2}{3}.\]

\[\textbf{г)}\ 16x² - 49 = 0\]

\[(4x - 7)(4x + 7) = 0\]

\[4x = 7\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ или\ \ \ \ \ \ \ 4x = - 7\]

\[x = \frac{7}{4} = 1,75\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x = - \frac{7}{4} = - 1,75\ \]

\[Ответ:x = \pm 1,75.\]