\[\boxed{\mathbf{108}.}\]
\[Приведенное\ квадратное\ \]
\[уравнение:\]
\[x^{2} + bx + c = 0.\]
\[x_{1} + x_{2} = - b;\ \ \ x_{1} \cdot x_{2} = c.\]
\[1)\ x_{1} = 3;\ \ x_{2} = - 7:\]
\[x_{1} + x_{2} = 3 - 7 = - 4 \rightarrow b = 4;\]
\[x_{1} \cdot x_{2} = 3 \cdot ( - 7) =\]
\[= - 21 \rightarrow c = - 21.\]
\[Уравнение\ имеет\ вид:\]
\[x^{2} + 4x - 21 = 0.\]
\[2)\ x_{1} = - 4;\ \ x_{2} = 0:\]
\[x_{1} + x_{2} = - 4 + 0 =\]
\[= - 4 \rightarrow b = 4.\]
\[x_{1} \cdot x_{2} = - 4 \cdot 0 = 0 \rightarrow c = 0.\]
\[Уравнение\ имеет\ вид:\]
\[x^{2} + 4x = 0.\]