\[- \frac{1}{8}x^{2} - \frac{3}{4}x + 5 = 0\ \ | \cdot ( - 8)\]
\[x^{2} + 6x - 40 = 0\]
\[x_{1} + x_{2} = - 6;\ \ \ x_{1} \cdot x_{2} = - 40\]
\[\Longrightarrow x_{1} = 4;\ \ x_{2} = - 10.\]
\[- \frac{1}{8}x^{2} - \frac{3}{4}x + 5 =\]
\[= - \frac{1}{8} \cdot (x - 4)(x + 10).\]