\[x^{2} + 3x - 8 = 0\]
\[\left\{ \begin{matrix} x_{1} + x_{2} = - 3\ \ \ (1) \\ x_{1} \cdot x_{2} = - 8\ \ \ (2)\ \ \\ \end{matrix} \right.\ \]
\[{(1)\text{\ x}}_{1} + 2 + x_{2} + 2 =\]
\[= x_{1} + x_{2} + 4 = - 3 + 4 = 1.\]
\[b = - 1.\]
\[(2)\ \left( x_{1} + 2 \right)\left( x_{2} + 2 \right) =\]
\[= x_{1}x_{2} + 2x_{1} + 2x_{2} + 4 =\]
\[= x_{1}x_{2} + 2 \cdot \left( x_{1} + x_{2} \right) + 4 =\]
\[= - 8 + 2 \cdot ( - 3) + 4 =\]
\[= - 8 - 6 + 4 = - 10.\]
\[c = - 10.\]
\[Получаем\ уравнение:\]
\[x² - x - 10 = 0.\]