[tex]\begin{gathered} \text{ x}^2\text{ + 3x - 4} \\ a\text{ = 1 b = 3 c = -4} \\ x\text{ = }\frac{-b\text{ }\pm\text{ }\sqrt[]{b^2\text{ - 4ac}}}{2a} \\ \text{Substitution} \\ x\text{ = }\frac{-3\text{ }\pm\sqrt[]{3^2-\text{ 4(1)(-4)}}}{2(1)} \end{gathered}[/tex][tex]\begin{gathered} \text{ x = }\frac{-3\pm\sqrt[]{9+\text{ 16}}}{2} \\ \text{ x = }\frac{-3\pm\sqrt[]{25}}{2} \\ \text{ x = }\frac{-3\pm5}{2} \\ x_1\text{ = }\frac{-3\text{ + 5}}{2}\text{ = }\frac{2}{2}\text{ = 1} \\ x_2\text{ = }\frac{-3\text{ - 5}}{2}\text{ = }\frac{-8}{2}\text{ = -4} \end{gathered}[/tex][tex]\begin{gathered} \text{ x}_{\text{ 1}}\text{ = 1} \\ x_2\text{ = -4} \end{gathered}[/tex]
