Is this more self-destructive?

$\large \sum_{x=0}^\infty \dfrac{ (2x)! (5^x + 6^x) }{x!^2 \cdot 60^x }$

If the value of the series above is in the form of $\dfrac{\sqrt a + \sqrt b}6$ , where $a$ and $b$ are positive integers, find $a+b$ .