Решебник по алгебре 8 класс Мерзляк Задание 662

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\[1)\ 4x + 4 = 3x² + 5x - 10\]

\[3x^{2} + x - 14 = 0\]

\[D = 1 + 4 \cdot 3 \cdot 14 = 169\]

\[x = \frac{- 1 \pm \sqrt{169}}{6} = \frac{- 1 \pm 13}{6}\]

\[x_{1} = - \frac{7}{3} = - 2\frac{1}{3}\]

\[x_{2} = 2\]

\[Ответ:\ x = - 2\frac{1}{3};x = 2.\ \]

\[2)\ 10p² + 10p + 8 =\]

\[= 3p² - 10p + 11\]

\[7p^{2} + 20p - 3 = 0\]

\[D = 400 + 4 \cdot 3 \cdot 7 = 484\]

\[p = \frac{- 20 \pm \sqrt{484}}{7 \cdot 2} = \frac{- 20 \pm 22}{14}\]

\[p_{1} = \frac{1}{7}\]

\[p_{2} = - 3\]

\[Ответ:x = \frac{1}{7};\ x = - 3.\]