Решебник по алгебре и начала математического анализа 11 класс Алимов Задание 1324

\[\boxed{\mathbf{1324}\mathbf{.}}\]

\[1)\ x(x + 1) - (x + 2)(x + 3) + 9 =\]

\[= x(x + 4) - (x + 5)(x + 2)\]

\[x^{2} + x - x^{2} - 3x - 2x - 6 + 9 =\]

\[= x^{2} + 4x - x^{2} - 2x - 5x - 10\]

\[3 - 4x = - 3x - 10\]

\[- x = - 13\]

\[x = 13.\]

\[Ответ:\ \ x = 13.\]

\[2)\ 2(x + 3)(x + 1) + 8 =\]

\[= (2x + 1)(x + 5)\]

\[2x^{2} + 2x + 6x + 6 + 8 =\]

\[= 2x^{2} + 10x + x + 5\]

\[2x^{2} + 8x + 14 = 2x^{2} + 11x + 5\]

\[- 3x = - 9\]

\[x = 3.\]

\[Ответ:\ \ x = 3.\]