8x² + 4x - 112 = 0
To solve this equation, we can use the quadratic formula, as follows:
[tex]\begin{gathered} x_{1,2}=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ x_{1,2}=\frac{-4\pm\sqrt[]{4^2-4\cdot8\cdot(-112)}}{2\cdot8} \\ x_{1,2}=\frac{-4\pm\sqrt[]{16+3584^{}}}{16} \\ x_{1,2}=\frac{-4\pm\sqrt[]{3600^{}}}{16} \\ x_1=\frac{-4+60}{16}=3.5 \\ x_2=\frac{-4-60}{16}=-4 \end{gathered}[/tex]