Algebra

First, let's combine all like terms and moving all terms to one side. 

We get the equation

$6x^{2}-21x-31=0$

Using the quadratic equation, we find two values of x. we have

$x=\frac{\sqrt{1185}+21}{12}\\ x=\frac{-\sqrt{1185}+21}{12}$

Obviously, the first term of x is bigger, so taking that, we find our final answer as

$x=\frac{\sqrt{1185}+21}{12}$

Thanks! :)