Solve the following equation:

$$
\sqrt{(17-x)^{2}}=(3-\sqrt{x})^{2}
$$
Using the identity $\sqrt{a^{2}}=|a|$, we obtain the roots. $x_{1}=16, x_{2}=\frac{169}{9}$. Either we can avoid the extraneous roots with our constraints, or we must filter them out by substitution.