[tex]\begin{gathered} x^2 - 18x + 80 = 0 \hfill \\ \Rightarrow \left( {x - 10} \right)\left( {x - 8} \right) = 0 \hfill \\ \Rightarrow x = 10 \vee x = 8 \hfill \\ \end{gathered} [/tex]
[tex]\begin{gathered} x^2 - 4x - 96 = 0 \hfill \\ \Rightarrow \left( {x - 12} \right)\left( {x + 8} \right) = 0 \hfill \\ \Rightarrow x = 12 \vee x = - 8 \hfill \\ \end{gathered} [/tex]
[tex]\begin{gathered} x^2 - 17x + 52 = 0 \hfill \\ \Rightarrow \left( {x - 13} \right)\left( {x - 4} \right) = 0 \hfill \\ \Rightarrow x = 13 \vee x = 4 \hfill \\ \end{gathered} [/tex]
[tex]\begin{gathered} x^2 - 7x - 120 = 0 \hfill \\ \Rightarrow \left( {x + 8} \right)\left( {x - 15} \right) = 0 \hfill \\ \Rightarrow x = - 8 \vee x = 15 \hfill \\ \end{gathered} [/tex]
[tex]\begin{gathered} 4x^2 + 5x - 6 = 0 \hfill \\ \Rightarrow 4\left( {x + 2} \right)\left( {x - \frac{3} {4}} \right) = 0 \hfill \\ \Rightarrow x = - 2 \vee x = \frac{3} {4} \hfill \\ \end{gathered} [/tex]
[tex]\begin{gathered} 6x^2 + 5x - 1 = 0 \hfill \\ \Rightarrow 6\left( {x + 1} \right)\left( {x - \frac{1} {6}} \right) = 0 \hfill \\ \Rightarrow x = - 1 \vee x = \frac{1} {6} \hfill \\ \end{gathered} [/tex]
