Nested fight back!

Algebra Level 5

$x = \sqrt{19} + \dfrac{91}{{\sqrt{19}+\dfrac{91}{{\sqrt{19}+\dfrac{91}{{\sqrt{19}+\dfrac{91}{{\sqrt{19}+\dfrac{91}{x}}}}}}}}}$

Find $A^2_{}$ , where $A^{}_{}$ is the sum of the absolute values of all roots of the equation above.