Lipschitz continuity of implicit functions

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I am struggling on the following problem and I couldn't find a reference to answer that question.

Let $F$ be a function of two variables such that $F\in\mathscr{C}^{1, \infty}(\mathbb{R}_+\times\mathbb{R},\mathbb{R})$. The function $F$ is bounded and also Lipschitz w.r.t the two variables and we have that:

$$\forall x\in\mathbb{R}_+,\exists!y_x\in\mathbb{R}\text{ s.t., } F(x,y_x)=0.$$

Can we say under these strong assumptions that the implicit function mapping $x$ to $y_x$ is Lipschitz ?

Otherwize, what condition could be added to make it true ?

The problem behind:

I have a function $f_a$ depending on a positive real parameter $a$ that has only one root $x_a$. I want to prove that for all $a_1,a_2>0$, there exists a constant $K$ such that :

$$|x_{a_1}-x_{a_2}|\leq K|a_1-a_2|.$$

Thank you very much!