Were exactly did I go wrong in rationalizing denominator? The question is to rationalize: $\frac{\sqrt5}{\sqrt10 - \sqrt5}$ 
I stopped at $\sqrt50 + 1$ after multiplying by the conjugate and cancelling out everything because I knew at this point my answer is wrong. The correct answer should be $\sqrt 2 + 1$

$$\frac{\sqrt5}{\sqrt10 - \sqrt5}=\frac{\sqrt5}{\sqrt{10} - \sqrt5} \times\frac{\sqrt{10} + \sqrt5}{\sqrt{10} + \sqrt5}=\frac{\sqrt5 (\sqrt{10} + \sqrt5)}{10-5}=\frac{\sqrt{10} + \sqrt5}{\sqrt5}=\sqrt2 +1$$
