Solve an equation in which a variable is an argument of a tangent: $x= K+y\tan(\sqrt{y})+y$

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What would you do if you need to find a relation between two variables but the one that you need to find in function of the other is the argument of a tangent ($\tan(y)$) ? For example if I have the equation: $$x= K+y\tan(\sqrt{y})+y$$ How do you find the $y$ in function of $x$? I need it to determine a dispersion relation and I want to avoid graphical solutions.

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When you give an implicit function definition, finding y=f(x) explicitly is not guaranteed (and oftentimes impossible).

What you could do could be to solve numerically, that is, loop for x in a certain range and search for an approximate solution s.t. x-h(x,y) ~ 0. You can use any root finding algorithm that you would like, Newton, bisection ...