[tex]3a^2-8a-60[/tex]
We will factorize using quadratic formula, like this:
[tex]\frac{8\pm\sqrt[]{64-4\cdot3\cdot(-60)}}{2\cdot3}[/tex][tex]\frac{8\pm\sqrt[]{64+720}}{6}[/tex][tex]\frac{8\pm\sqrt[]{784}}{6}[/tex][tex]\frac{8\pm28}{6}[/tex]
We have two options:
[tex]\frac{8-28}{6}=\frac{-20}{6}=\frac{-10}{3}[/tex]
And
[tex]\frac{8+28}{6}=\frac{36}{6}=6[/tex]
So, the factors of the original function are:
[tex]3a^2-8a-60=(a-6)(3a+10)[/tex]
