Решебник по алгебре 9 класс Макарычев Задание 402

 

\[\boxed{\text{402.}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[\textbf{а)}\ xy = 6\]

\[y = \frac{6}{x}\]

\[\textbf{б)}\ y - 0,5x^{2} = 1\]

\[y = 0,5x^{2} + 1\]

\[\textbf{в)}\ x^{2} + y^{2} = 9\]

\[Окружность\ с\ центром\ (0;0)\ \]

\[и\ радиусом\ r = 3.\]

\[\textbf{г)}\ (x + 1)^{2} + (y - 1)^{2} = 4\]

\[Окружность\ с\ центром\ \]

\[( - 1;1)\ и\ радиусом\ r = 2.\]

\(\boxed{\text{402.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\)

\[x - y = - 7\]

\[y = x + 7;\]

\[x^{2} + y^{2} = 36\]

\[( - 6;1);\ \ ( - 1;6).\]

\[x^{2} + x^{2} + 14x + 49 - 36 = 0\]

\[2x^{2} + 14x + 13 = 0\]

\[D_{1} = 49 - 26 = 23\]

\[x_{1} = \frac{- 7 + \sqrt{23}}{3} \approx - 1;\]

\[x_{2} = \frac{- 7 - \sqrt{23}}{3} \approx - 6.\]

\[y_{1} = - 1 + 7 = 6;\]

\[y_{2} = - 6 + 7 = 1.\]