Another way of rationalising denominator

• I like to rationalise denominators this way:
There’s a $$\sqrt{2}$$ in the denominator, so to get rid of that, we need a $$\sqrt{2}$$ in the numerator.
Luckily, $$10$$ is made of $$\sqrt{2} \times 5 \sqrt{2}$$.
Cancellong out the two $$\sqrt{2}$$‘s in the numerator and the denominator, we get $$5 \sqrt{2}$$.